Merge pull request #8125 from eugenp/revert-8119-BAEL-3275-2

Revert "BAEL-3275: Using blocking queue for pub-sub"

spring-mvc-java/src/main/java/com/baeldung/SpringMVCApplication.java

@@ -0,0 +1,12 @@
+package com.baeldung;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
+
+@SpringBootApplication
+public class SpringMVCApplication extends SpringBootServletInitializer {
+    public static void main(String[] args) {
+        SpringApplication.run(SpringMVCApplication.class, args);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/aop/LoggingAspect.java

@@ -0,0 +1,54 @@
+package com.baeldung.aop;
+
+import org.aspectj.lang.JoinPoint;
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Before;
+import org.aspectj.lang.annotation.Pointcut;
+import org.springframework.stereotype.Component;
+
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.logging.Logger;
+
+@Component
+@Aspect
+public class LoggingAspect {
+
+    private static Logger logger = Logger.getLogger(LoggingAspect.class.getName());
+
+    private ThreadLocal<SimpleDateFormat> sdf = new ThreadLocal<SimpleDateFormat>() {
+        @Override
+        protected SimpleDateFormat initialValue() {
+            return new SimpleDateFormat("[yyyy-mm-dd hh:mm:ss:SSS]");
+        }
+    };
+
+    @Pointcut("within(com.baeldung..*) && execution(* com.baeldung.dao.FooDao.*(..))")
+    public void repositoryMethods() {
+    }
+
+    @Pointcut("within(com.baeldung..*) && @annotation(com.baeldung.aop.annotations.Loggable)")
+    public void loggableMethods() {
+    }
+
+    @Pointcut("within(com.baeldung..*) && @args(com.baeldung.aop.annotations.Entity)")
+    public void methodsAcceptingEntities() {
+    }
+
+    @Before("repositoryMethods()")
+    public void logMethodCall(JoinPoint jp) {
+        String methodName = jp.getSignature().getName();
+        logger.info(sdf.get().format(new Date()) + methodName);
+    }
+
+    @Before("loggableMethods()")
+    public void logMethod(JoinPoint jp) {
+        String methodName = jp.getSignature().getName();
+        logger.info("Executing method: " + methodName);
+    }
+
+    @Before("methodsAcceptingEntities()")
+    public void logMethodAcceptionEntityAnnotatedBean(JoinPoint jp) {
+        logger.info("Accepting beans with @Entity annotation: " + jp.getArgs()[0]);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/aop/PerformanceAspect.java

@@ -0,0 +1,32 @@
+package com.baeldung.aop;
+
+import org.aspectj.lang.ProceedingJoinPoint;
+import org.aspectj.lang.annotation.Around;
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Pointcut;
+import org.springframework.stereotype.Component;
+
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Logger;
+
+@Aspect
+@Component
+public class PerformanceAspect {
+
+    private static Logger logger = Logger.getLogger(PerformanceAspect.class.getName());
+
+    @Pointcut("within(com.baeldung..*) && execution(* com.baeldung.dao.FooDao.*(..))")
+    public void repositoryClassMethods() {
+    }
+
+    @Around("repositoryClassMethods()")
+    public Object measureMethodExecutionTime(ProceedingJoinPoint pjp) throws Throwable {
+        long start = System.nanoTime();
+        Object retval = pjp.proceed();
+        long end = System.nanoTime();
+        String methodName = pjp.getSignature().getName();
+        logger.info("Execution of " + methodName + " took " + TimeUnit.NANOSECONDS.toMillis(end - start) + " ms");
+        return retval;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/aop/PublishingAspect.java

@@ -0,0 +1,39 @@
+package com.baeldung.aop;
+
+import com.baeldung.events.FooCreationEvent;
+import org.aspectj.lang.JoinPoint;
+import org.aspectj.lang.annotation.AfterReturning;
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Pointcut;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.stereotype.Component;
+
+@Component
+@Aspect
+public class PublishingAspect {
+
+    private ApplicationEventPublisher eventPublisher;
+
+    @Autowired
+    public void setEventPublisher(ApplicationEventPublisher eventPublisher) {
+        this.eventPublisher = eventPublisher;
+    }
+
+    @Pointcut("within(com.baeldung..*) && execution(* com.baeldung.dao.FooDao.*(..))")
+    public void repositoryMethods() {
+    }
+
+    @Pointcut("within(com.baeldung..*) && execution(* com.baeldung.dao.FooDao.create*(Long,..))")
+    public void firstLongParamMethods() {
+    }
+
+    @Pointcut("repositoryMethods() && firstLongParamMethods()")
+    public void entityCreationMethods() {
+    }
+
+    @AfterReturning(value = "entityCreationMethods()", returning = "entity")
+    public void logMethodCall(JoinPoint jp, Object entity) throws Throwable {
+        eventPublisher.publishEvent(new FooCreationEvent(entity));
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/aop/annotations/Entity.java

@@ -0,0 +1,11 @@
+package com.baeldung.aop.annotations;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface Entity {
+}

spring-mvc-java/src/main/java/com/baeldung/aop/annotations/Loggable.java

@@ -0,0 +1,11 @@
+package com.baeldung.aop.annotations;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface Loggable {
+}

spring-mvc-java/src/main/java/com/baeldung/cache/BookService.java

@@ -0,0 +1,21 @@
+package com.baeldung.cache;
+
+import com.baeldung.model.Book;
+import org.springframework.cache.annotation.Cacheable;
+import org.springframework.stereotype.Component;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Component
+public class BookService {
+
+    @Cacheable(value="books", keyGenerator="customKeyGenerator")
+    public List<Book> getBooks() {
+        List<Book> books = new ArrayList<Book>();
+        books.add(new Book(1, "The Counterfeiters", "André Gide"));
+        books.add(new Book(2, "Peer Gynt and Hedda Gabler", "Henrik Ibsen"));
+        return books;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/cache/CustomKeyGenerator.java

@@ -0,0 +1,14 @@
+package com.baeldung.cache;
+
+import org.springframework.cache.interceptor.KeyGenerator;
+import org.springframework.util.StringUtils;
+
+import java.lang.reflect.Method;
+
+public class CustomKeyGenerator implements KeyGenerator {
+
+    public Object generate(Object target, Method method, Object... params) {
+        return target.getClass().getSimpleName() + "_" + method.getName() + "_"
+                + StringUtils.arrayToDelimitedString(params, "_");
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/dao/FooDao.java

@@ -0,0 +1,22 @@
+package com.baeldung.dao;
+
+import com.baeldung.aop.annotations.Loggable;
+import com.baeldung.model.Foo;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public class FooDao {
+
+    public String findById(Long id) {
+        return "Bazz";
+    }
+
+    @Loggable
+    public Foo create(Long id, String name) {
+        return new Foo(id, name);
+    }
+
+    public Foo merge(Foo foo) {
+        return foo;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/datetime/DateTimeConfig.java

@@ -0,0 +1,29 @@
+package com.baeldung.datetime;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.format.datetime.standard.DateTimeFormatterRegistrar;
+import org.springframework.format.number.NumberFormatAnnotationFormatterFactory;
+import org.springframework.format.support.DefaultFormattingConversionService;
+import org.springframework.format.support.FormattingConversionService;
+
+import java.time.format.DateTimeFormatter;
+
+@Configuration
+class DateTimeConfig {
+
+    @Bean
+    public FormattingConversionService conversionService() {
+        DefaultFormattingConversionService conversionService = new DefaultFormattingConversionService(false);
+
+        conversionService.addFormatterForFieldAnnotation(new NumberFormatAnnotationFormatterFactory());
+
+        DateTimeFormatterRegistrar registrar = new DateTimeFormatterRegistrar();
+        registrar.setDateFormatter(DateTimeFormatter.ofPattern("dd.MM.yyyy"));
+        registrar.setDateTimeFormatter(DateTimeFormatter.ofPattern("dd.MM.yyyy HH:mm:ss"));
+        registrar.registerFormatters(conversionService);
+
+        return conversionService;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/datetime/DateTimeController.java

@@ -0,0 +1,29 @@
+package com.baeldung.datetime;
+
+import org.springframework.format.annotation.DateTimeFormat;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.util.Date;
+
+@RestController
+public class DateTimeController {
+
+    @PostMapping("/date")
+    public void date(@RequestParam("date") @DateTimeFormat(pattern = "dd.MM.yyyy") Date date) {
+        // ...
+    }
+
+    @PostMapping("/localdate")
+    public void localDate(@RequestParam("localDate") @DateTimeFormat(iso = DateTimeFormat.ISO.DATE) LocalDate localDate) {
+        // ...
+    }
+
+    @PostMapping("/localdatetime")
+    public void dateTime(@RequestParam("localDateTime") @DateTimeFormat(iso = DateTimeFormat.ISO.DATE_TIME) LocalDateTime localDateTime) {
+        // ...
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/events/FooCreationEvent.java

@@ -0,0 +1,10 @@
+package com.baeldung.events;
+
+import org.springframework.context.ApplicationEvent;
+
+public class FooCreationEvent extends ApplicationEvent {
+
+    public FooCreationEvent(Object source) {
+        super(source);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/events/FooCreationEventListener.java

@@ -0,0 +1,17 @@
+package com.baeldung.events;
+
+import org.springframework.context.ApplicationListener;
+import org.springframework.stereotype.Component;
+
+import java.util.logging.Logger;
+
+@Component
+public class FooCreationEventListener implements ApplicationListener<FooCreationEvent> {
+
+    private static Logger logger = Logger.getLogger(FooCreationEventListener.class.getName());
+
+    @Override
+    public void onApplicationEvent(FooCreationEvent event) {
+        logger.info("Created foo instance: " + event.getSource().toString());
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/excel/ExcelPOIHelper.java

@@ -0,0 +1,185 @@
+package com.baeldung.excel;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.xssf.usermodel.XSSFCell;
+import org.apache.poi.xssf.usermodel.XSSFCellStyle;
+import org.apache.poi.xssf.usermodel.XSSFColor;
+import org.apache.poi.xssf.usermodel.XSSFFont;
+import org.apache.poi.xssf.usermodel.XSSFRow;
+import org.apache.poi.xssf.usermodel.XSSFSheet;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.apache.poi.hssf.usermodel.HSSFCell;
+import org.apache.poi.hssf.usermodel.HSSFCellStyle;
+import org.apache.poi.hssf.usermodel.HSSFFont;
+import org.apache.poi.hssf.usermodel.HSSFRow;
+import org.apache.poi.hssf.usermodel.HSSFSheet;
+import org.apache.poi.hssf.usermodel.HSSFWorkbook;
+import org.apache.poi.hssf.util.HSSFColor;
+import org.apache.poi.ss.usermodel.DateUtil;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.Map;
+import java.util.HashMap;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.IntStream;
+
+public class ExcelPOIHelper {
+
+    public Map<Integer, List<MyCell>> readExcel(String fileLocation) throws IOException {
+
+        Map<Integer, List<MyCell>> data = new HashMap<>();
+        FileInputStream fis = new FileInputStream(new File(fileLocation));
+
+        if (fileLocation.endsWith(".xls")) {
+            data = readHSSFWorkbook(fis);
+        } else if (fileLocation.endsWith(".xlsx")) {
+            data = readXSSFWorkbook(fis);
+        }
+
+        int maxNrCols = data.values().stream()
+          .mapToInt(List::size)
+          .max()
+          .orElse(0);
+
+        data.values().stream()
+          .filter(ls -> ls.size() < maxNrCols)
+          .forEach(ls -> {
+              IntStream.range(ls.size(), maxNrCols)
+                .forEach(i -> ls.add(new MyCell("")));
+          });
+
+        return data;
+    }
+
+    private String readCellContent(Cell cell) {
+        String content;
+        switch (cell.getCellTypeEnum()) {
+        case STRING:
+            content = cell.getStringCellValue();
+            break;
+        case NUMERIC:
+            if (DateUtil.isCellDateFormatted(cell)) {
+                content = cell.getDateCellValue() + "";
+            } else {
+                content = cell.getNumericCellValue() + "";
+            }
+            break;
+        case BOOLEAN:
+            content = cell.getBooleanCellValue() + "";
+            break;
+        case FORMULA:
+            content = cell.getCellFormula() + "";
+            break;
+        default:
+            content = "";
+        }
+        return content;
+    }
+
+    private Map<Integer, List<MyCell>> readHSSFWorkbook(FileInputStream fis) throws IOException {
+        Map<Integer, List<MyCell>> data = new HashMap<>();
+        HSSFWorkbook workbook = null;
+        try {
+            workbook = new HSSFWorkbook(fis);
+
+            HSSFSheet sheet = workbook.getSheetAt(0);
+            for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {
+                HSSFRow row = sheet.getRow(i);
+                data.put(i, new ArrayList<>());
+                if (row != null) {
+                    for (int j = 0; j < row.getLastCellNum(); j++) {
+                        HSSFCell cell = row.getCell(j);
+                        if (cell != null) {
+                            HSSFCellStyle cellStyle = cell.getCellStyle();
+
+                            MyCell myCell = new MyCell();
+
+                            HSSFColor bgColor = cellStyle.getFillForegroundColorColor();
+                            if (bgColor != null) {
+                                short[] rgbColor = bgColor.getTriplet();
+                                myCell.setBgColor("rgb(" + rgbColor[0] + "," + rgbColor[1] + "," + rgbColor[2] + ")");
+                            }
+                            HSSFFont font = cell.getCellStyle()
+                                .getFont(workbook);
+                            myCell.setTextSize(font.getFontHeightInPoints() + "");
+                            if (font.getBold()) {
+                                myCell.setTextWeight("bold");
+                            }
+                            HSSFColor textColor = font.getHSSFColor(workbook);
+                            if (textColor != null) {
+                                short[] rgbColor = textColor.getTriplet();
+                                myCell.setTextColor("rgb(" + rgbColor[0] + "," + rgbColor[1] + "," + rgbColor[2] + ")");
+                            }
+                            myCell.setContent(readCellContent(cell));
+                            data.get(i)
+                                .add(myCell);
+                        } else {
+                            data.get(i)
+                                .add(new MyCell(""));
+                        }
+                    }
+                }
+            }
+        } finally {
+            if (workbook != null) {
+                workbook.close();
+            }
+        }
+        return data;
+    }
+
+    private Map<Integer, List<MyCell>> readXSSFWorkbook(FileInputStream fis) throws IOException {
+        XSSFWorkbook workbook = null;
+        Map<Integer, List<MyCell>> data = new HashMap<>();
+        try {
+
+            workbook = new XSSFWorkbook(fis);
+            XSSFSheet sheet = workbook.getSheetAt(0);
+
+            for (int i = sheet.getFirstRowNum(); i <= sheet.getLastRowNum(); i++) {
+                XSSFRow row = sheet.getRow(i);
+                data.put(i, new ArrayList<>());
+                if (row != null) {
+                    for (int j = 0; j < row.getLastCellNum(); j++) {
+                        XSSFCell cell = row.getCell(j);
+                        if (cell != null) {
+                            XSSFCellStyle cellStyle = cell.getCellStyle();
+
+                            MyCell myCell = new MyCell();
+                            XSSFColor bgColor = cellStyle.getFillForegroundColorColor();
+                            if (bgColor != null) {
+                                byte[] rgbColor = bgColor.getRGB();
+                                myCell.setBgColor("rgb(" + (rgbColor[0] < 0 ? (rgbColor[0] + 0xff) : rgbColor[0]) + "," + (rgbColor[1] < 0 ? (rgbColor[1] + 0xff) : rgbColor[1]) + "," + (rgbColor[2] < 0 ? (rgbColor[2] + 0xff) : rgbColor[2]) + ")");
+                            }
+                            XSSFFont font = cellStyle.getFont();
+                            myCell.setTextSize(font.getFontHeightInPoints() + "");
+                            if (font.getBold()) {
+                                myCell.setTextWeight("bold");
+                            }
+                            XSSFColor textColor = font.getXSSFColor();
+                            if (textColor != null) {
+                                byte[] rgbColor = textColor.getRGB();
+                                myCell.setTextColor("rgb(" + (rgbColor[0] < 0 ? (rgbColor[0] + 0xff) : rgbColor[0]) + "," + (rgbColor[1] < 0 ? (rgbColor[1] + 0xff) : rgbColor[1]) + "," + (rgbColor[2] < 0 ? (rgbColor[2] + 0xff) : rgbColor[2]) + ")");
+                            }
+                            myCell.setContent(readCellContent(cell));
+                            data.get(i)
+                                .add(myCell);
+                        } else {
+                            data.get(i)
+                                .add(new MyCell(""));
+                        }
+                    }
+                }
+            }
+        } finally {
+            if (workbook != null) {
+                workbook.close();
+            }
+        }
+        return data;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/excel/MyCell.java

@@ -0,0 +1,57 @@
+package com.baeldung.excel;
+
+public class MyCell {
+    private String content;
+    private String textColor;
+    private String bgColor;
+    private String textSize;
+    private String textWeight;
+
+    public MyCell() {
+    }
+
+    public MyCell(String content) {
+        this.content = content;
+    }
+
+    public String getContent() {
+        return content;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    public String getTextColor() {
+        return textColor;
+    }
+
+    public void setTextColor(String textColor) {
+        this.textColor = textColor;
+    }
+
+    public String getBgColor() {
+        return bgColor;
+    }
+
+    public void setBgColor(String bgColor) {
+        this.bgColor = bgColor;
+    }
+
+    public String getTextSize() {
+        return textSize;
+    }
+
+    public void setTextSize(String textSize) {
+        this.textSize = textSize;
+    }
+
+    public String getTextWeight() {
+        return textWeight;
+    }
+
+    public void setTextWeight(String textWeight) {
+        this.textWeight = textWeight;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/filters/EmptyParamFilter.java

@@ -0,0 +1,35 @@
+package com.baeldung.filters;
+
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.annotation.WebFilter;
+import java.io.IOException;
+
+@WebFilter(urlPatterns = "/uppercase")
+public class EmptyParamFilter implements Filter {
+
+    @Override
+    public void init(FilterConfig filterConfig) throws ServletException {
+    }
+
+    @Override
+    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse,
+        FilterChain filterChain) throws IOException, ServletException {
+        String inputString = servletRequest.getParameter("input");
+
+        if (inputString != null && inputString.matches("[A-Za-z0-9]+")) {
+            filterChain.doFilter(servletRequest, servletResponse);
+        } else {
+            servletResponse.getWriter().println("Missing input parameter");
+        }
+    }
+
+    @Override
+    public void destroy() {
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/listeners/AppListener.java

@@ -0,0 +1,21 @@
+package com.baeldung.listeners;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletContextEvent;
+import javax.servlet.ServletContextListener;
+import javax.servlet.annotation.WebListener;
+
+@WebListener
+public class AppListener implements ServletContextListener {
+
+    @Override
+    public void contextInitialized(ServletContextEvent event) {
+        ServletContext context = event.getServletContext();
+        context.setAttribute("counter", 0);
+    }
+
+    @Override
+    public void contextDestroyed(ServletContextEvent event) {
+
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/listeners/RequestListener.java

@@ -0,0 +1,24 @@
+package com.baeldung.listeners;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletRequestEvent;
+import javax.servlet.ServletRequestListener;
+import javax.servlet.annotation.WebListener;
+import javax.servlet.http.HttpServletRequest;
+
+@WebListener
+public class RequestListener implements ServletRequestListener {
+
+    @Override
+    public void requestInitialized(ServletRequestEvent event) {
+    }
+
+    @Override
+    public void requestDestroyed(ServletRequestEvent event) {
+        HttpServletRequest request = (HttpServletRequest)event.getServletRequest();
+        if (!request.getServletPath().equals("/counter")) {
+            ServletContext context = event.getServletContext();
+            context.setAttribute("counter", (int)context.getAttribute("counter") + 1);
+        }
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/model/Book.java

@@ -0,0 +1,42 @@
+package com.baeldung.model;
+
+public class Book {
+
+    private int id;
+    private String author;
+    private String title;
+
+    public Book() {
+    }
+
+    public Book(int id, String author, String title) {
+        this.id = id;
+        this.author = author;
+        this.title = title;
+    }
+
+    public int getId() {
+        return id;
+    }
+    
+    public void setId(int id) {
+        this.id = id;
+    }
+    
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+    
+}

spring-mvc-java/src/main/java/com/baeldung/model/Company.java

@@ -0,0 +1,38 @@
+package com.baeldung.model;
+
+public class Company {
+
+    private long id;
+    private String name;
+
+    public Company() {
+        super();
+    }
+
+    public Company(final long id, final String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(final String name) {
+        this.name = name;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(final long id) {
+        this.id = id;
+    }
+
+    @Override
+    public String toString() {
+        return "Company [id=" + id + ", name=" + name + "]";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/model/Employee.java

@@ -0,0 +1,61 @@
+package com.baeldung.model;
+
+import javax.xml.bind.annotation.XmlRootElement;
+
+@XmlRootElement
+public class Employee {
+
+    private long id;
+    private String name;
+    private String contactNumber;
+    private String workingArea;
+
+    public Employee() {
+        super();
+    }
+
+    public Employee(final long id, final String name, final String contactNumber, final String workingArea) {
+        this.id = id;
+        this.name = name;
+        this.contactNumber = contactNumber;
+        this.workingArea = workingArea;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(final String name) {
+        this.name = name;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(final long id) {
+        this.id = id;
+    }
+
+    public String getContactNumber() {
+        return contactNumber;
+    }
+
+    public void setContactNumber(final String contactNumber) {
+        this.contactNumber = contactNumber;
+    }
+
+    public String getWorkingArea() {
+        return workingArea;
+    }
+
+    public void setWorkingArea(final String workingArea) {
+        this.workingArea = workingArea;
+    }
+
+    @Override
+    public String toString() {
+        return "Employee [id=" + id + ", name=" + name + ", contactNumber=" + contactNumber + ", workingArea=" + workingArea + "]";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/model/Foo.java

@@ -0,0 +1,19 @@
+package com.baeldung.model;
+
+import com.baeldung.aop.annotations.Entity;
+
+@Entity
+public class Foo {
+    private Long id;
+    private String name;
+
+    public Foo(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return "Foo{" + "id=" + id + ", name='" + name + '\'' + '}';
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/model/FormDataWithFile.java

@@ -0,0 +1,35 @@
+package com.baeldung.model;
+
+import org.springframework.web.multipart.MultipartFile;
+
+public class FormDataWithFile {
+
+    private String name;
+    private String email;
+    private MultipartFile file;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public MultipartFile getFile() {
+        return file;
+    }
+
+    public void setFile(MultipartFile file) {
+        this.file = file;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/model/Greeting.java

@@ -0,0 +1,22 @@
+package com.baeldung.model;
+
+public class Greeting {
+    private int id;
+    private String message;
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/model/Message.java

@@ -0,0 +1,15 @@
+package com.baeldung.model;
+
+public class Message {
+
+    private String from;
+    private String text;
+
+    public String getText() {
+        return text;
+    }
+
+    public String getFrom() {
+        return from;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/model/OutputMessage.java

@@ -0,0 +1,27 @@
+package com.baeldung.model;
+
+public class OutputMessage {
+
+    private String from;
+    private String text;
+    private String time;
+
+    public OutputMessage(final String from, final String text, final String time) {
+
+        this.from = from;
+        this.text = text;
+        this.time = time;
+    }
+
+    public String getText() {
+        return text;
+    }
+
+    public String getTime() {
+        return time;
+    }
+
+    public String getFrom() {
+        return from;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/model/User.java

@@ -0,0 +1,32 @@
+package com.baeldung.model;
+
+public class User {
+    private String firstname;
+    private String lastname;
+    private String emailId;
+
+    public String getFirstname() {
+        return firstname;
+    }
+
+    public void setFirstname(final String firstname) {
+        this.firstname = firstname;
+    }
+
+    public String getLastname() {
+        return lastname;
+    }
+
+    public void setLastname(final String lastname) {
+        this.lastname = lastname;
+    }
+
+    public String getEmailId() {
+        return emailId;
+    }
+
+    public void setEmailId(final String emailId) {
+        this.emailId = emailId;
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/servlets/CounterServlet.java

@@ -0,0 +1,21 @@
+package com.baeldung.servlets;
+
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.io.PrintWriter;
+
+@WebServlet(urlPatterns = "/counter", name = "counterServlet")
+public class CounterServlet extends HttpServlet {
+
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
+        PrintWriter out = response.getWriter();
+
+        int count = (int)request.getServletContext().getAttribute("counter");
+
+        out.println("Request counter: " + count);
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/servlets/UppercaseServlet.java

@@ -0,0 +1,20 @@
+package com.baeldung.servlets;
+
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.io.PrintWriter;
+
+@WebServlet(urlPatterns = "/uppercase", name = "uppercaseServlet")
+public class UppercaseServlet extends HttpServlet {
+
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
+        String inputString = request.getParameter("input").toUpperCase();
+
+        PrintWriter out = response.getWriter();
+
+        out.println(inputString);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/ApplicationCacheConfig.java

@@ -0,0 +1,32 @@
+package com.baeldung.spring.web.config;
+
+import com.baeldung.cache.CustomKeyGenerator;
+import org.springframework.cache.Cache;
+import org.springframework.cache.CacheManager;
+import org.springframework.cache.annotation.CachingConfigurerSupport;
+import org.springframework.cache.annotation.EnableCaching;
+import org.springframework.cache.concurrent.ConcurrentMapCache;
+import org.springframework.cache.interceptor.KeyGenerator;
+import org.springframework.cache.support.SimpleCacheManager;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import java.util.Arrays;
+
+@EnableCaching
+@Configuration
+public class ApplicationCacheConfig extends CachingConfigurerSupport {
+
+    @Bean
+    public CacheManager cacheManager() {
+        SimpleCacheManager cacheManager = new SimpleCacheManager();
+        Cache booksCache = new ConcurrentMapCache("books");
+        cacheManager.setCaches(Arrays.asList(booksCache));
+        return cacheManager;
+    }
+
+    @Bean("customKeyGenerator")
+    public KeyGenerator keyGenerator() {
+        return new CustomKeyGenerator();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/CustomWebMvcConfigurationSupport.java

@@ -0,0 +1,17 @@
+package com.baeldung.spring.web.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
+import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
+
+@Configuration
+public class CustomWebMvcConfigurationSupport extends WebMvcConfigurationSupport {
+
+    @Bean
+    public RequestMappingHandlerMapping requestMappingHandlerMapping() {
+        RequestMappingHandlerMapping handlerMapping = super.requestMappingHandlerMapping();
+        handlerMapping.setUseSuffixPatternMatch(false);
+        return handlerMapping;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/WebConfig.java

@@ -0,0 +1,124 @@
+package com.baeldung.spring.web.config;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.springframework.context.MessageSource;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Description;
+import org.springframework.context.support.ResourceBundleMessageSource;
+import org.springframework.http.MediaType;
+import org.springframework.http.converter.ByteArrayHttpMessageConverter;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.web.servlet.ViewResolver;
+import org.springframework.web.servlet.config.annotation.EnableWebMvc;
+import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
+import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
+import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import org.springframework.web.servlet.view.InternalResourceViewResolver;
+import org.springframework.web.servlet.view.JstlView;
+import org.springframework.web.util.UrlPathHelper;
+import org.thymeleaf.spring4.SpringTemplateEngine;
+import org.thymeleaf.spring4.templateresolver.SpringResourceTemplateResolver;
+import org.thymeleaf.spring4.view.ThymeleafViewResolver;
+import org.thymeleaf.templateresolver.ITemplateResolver;
+
+import com.baeldung.excel.ExcelPOIHelper;
+
+@EnableWebMvc
+@Configuration
+@ComponentScan(basePackages = { "com.baeldung.web.controller" })
+public class WebConfig implements WebMvcConfigurer {
+	
+    @Override
+    public void addViewControllers(final ViewControllerRegistry registry) {
+        registry.addViewController("/").setViewName("index");
+    }
+    
+    @Bean
+    public ViewResolver thymeleafViewResolver() {
+        final ThymeleafViewResolver viewResolver = new ThymeleafViewResolver();
+        viewResolver.setTemplateEngine(templateEngine());
+        viewResolver.setOrder(1);
+        return viewResolver;
+    }
+
+    @Bean
+    public ViewResolver viewResolver() {
+        final InternalResourceViewResolver bean = new InternalResourceViewResolver();
+        bean.setViewClass(JstlView.class);
+        bean.setPrefix("/WEB-INF/view/");
+        bean.setSuffix(".jsp");
+        bean.setOrder(0);
+        return bean;
+    }
+
+    @Bean
+    @Description("Thymeleaf template resolver serving HTML 5")
+    public ITemplateResolver templateResolver() {
+        final SpringResourceTemplateResolver templateResolver = new SpringResourceTemplateResolver();
+        templateResolver.setPrefix("/WEB-INF/templates/");
+        templateResolver.setSuffix(".html");
+        templateResolver.setTemplateMode("HTML");
+        return templateResolver;
+    }
+
+    @Bean
+    @Description("Thymeleaf template engine with Spring integration")
+    public SpringTemplateEngine templateEngine() {
+        final SpringTemplateEngine templateEngine = new SpringTemplateEngine();
+        templateEngine.setTemplateResolver(templateResolver());
+        return templateEngine;
+    }
+
+    @Bean
+    @Description("Spring message resolver")
+    public MessageSource messageSource() {
+        final ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
+        messageSource.setBasename("messages");
+        return messageSource;
+    }
+
+    @Override
+    public void addResourceHandlers(final ResourceHandlerRegistry registry) {
+        registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
+    }
+
+    @Override
+    public void extendMessageConverters(final List<HttpMessageConverter<?>> converters) {
+        converters.add(byteArrayHttpMessageConverter());
+    }
+
+    @Bean
+    public ByteArrayHttpMessageConverter byteArrayHttpMessageConverter() {
+        final ByteArrayHttpMessageConverter arrayHttpMessageConverter = new ByteArrayHttpMessageConverter();
+        arrayHttpMessageConverter.setSupportedMediaTypes(getSupportedMediaTypes());
+
+        return arrayHttpMessageConverter;
+    }
+
+    private List<MediaType> getSupportedMediaTypes() {
+        final List<MediaType> list = new ArrayList<MediaType>();
+        list.add(MediaType.IMAGE_JPEG);
+        list.add(MediaType.IMAGE_PNG);
+        list.add(MediaType.APPLICATION_OCTET_STREAM);
+
+        return list;
+    }
+
+    @Override
+    public void configurePathMatch(final PathMatchConfigurer configurer) {
+        final UrlPathHelper urlPathHelper = new UrlPathHelper();
+        urlPathHelper.setRemoveSemicolonContent(false);
+
+        configurer.setUrlPathHelper(urlPathHelper);
+    }
+
+    @Bean
+    public ExcelPOIHelper excelPOIHelper() {
+        return new ExcelPOIHelper();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/WebSocketConfig.java

@@ -0,0 +1,25 @@
+package com.baeldung.spring.web.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.messaging.simp.config.MessageBrokerRegistry;
+import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
+import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
+import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
+
+@Configuration
+@EnableWebSocketMessageBroker
+public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
+
+    @Override
+    public void configureMessageBroker(final MessageBrokerRegistry config) {
+        config.enableSimpleBroker("/topic");
+        config.setApplicationDestinationPrefixes("/app");
+    }
+
+    @Override
+    public void registerStompEndpoints(final StompEndpointRegistry registry) {
+        registry.addEndpoint("/chat");
+        registry.addEndpoint("/chat").withSockJS();
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/spring/web/config/WebSocketSendToUserConfig.java

@@ -0,0 +1,42 @@
+package com.baeldung.spring.web.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.server.ServerHttpRequest;
+import org.springframework.http.server.ServerHttpResponse;
+import org.springframework.http.server.ServletServerHttpRequest;
+import org.springframework.messaging.simp.config.MessageBrokerRegistry;
+import org.springframework.web.socket.WebSocketHandler;
+import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
+import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
+import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;
+import org.springframework.web.socket.server.support.DefaultHandshakeHandler;
+
+import javax.servlet.http.HttpSession;
+import java.util.Map;
+
+@Configuration
+@EnableWebSocketMessageBroker
+public class WebSocketSendToUserConfig implements WebSocketMessageBrokerConfigurer {
+
+    @Override
+    public void configureMessageBroker(MessageBrokerRegistry config) {
+        config.enableSimpleBroker("/topic/", "/queue/");
+        config.setApplicationDestinationPrefixes("/app");
+    }
+
+    @Override
+    public void registerStompEndpoints(StompEndpointRegistry registry) {
+        registry.addEndpoint("/greeting").setHandshakeHandler(new DefaultHandshakeHandler() {
+
+            //Get sessionId from request and set it in Map attributes
+            public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler,
+                                             Map attributes) throws Exception {
+                if (request instanceof ServletServerHttpRequest) {
+                    ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request;
+                    HttpSession session = servletRequest.getServletRequest().getSession();
+                    attributes.put("sessionId", session.getId());
+                }
+                return true;
+            }}).withSockJS();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/BeanA.java

@@ -0,0 +1,15 @@
+package com.baeldung.web;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+@Component
+public class BeanA {
+
+    @Autowired
+    private BeanB b;
+
+    public BeanA() {
+        super();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/BeanB.java

@@ -0,0 +1,11 @@
+package com.baeldung.web;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class BeanB {
+
+    public BeanB() {
+        super();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/ChatController.java

@@ -0,0 +1,23 @@
+package com.baeldung.web.controller;
+
+import com.baeldung.model.Message;
+import com.baeldung.model.OutputMessage;
+import org.springframework.messaging.handler.annotation.MessageMapping;
+import org.springframework.messaging.handler.annotation.SendTo;
+import org.springframework.stereotype.Controller;
+
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+@Controller
+public class ChatController {
+
+    @MessageMapping("/chat")
+    @SendTo("/topic/messages")
+    public OutputMessage send(final Message message) throws Exception {
+
+        final String time = new SimpleDateFormat("HH:mm").format(new Date());
+        return new OutputMessage(message.getFrom(), message.getText(), time);
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/CompanyController.java

@@ -0,0 +1,63 @@
+package com.baeldung.web.controller;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.ModelMap;
+import org.springframework.validation.BindingResult;
+import org.springframework.web.bind.annotation.MatrixVariable;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.servlet.ModelAndView;
+
+import com.baeldung.model.Company;
+
+@Controller
+public class CompanyController {
+
+    Map<Long, Company> companyMap = new HashMap<>();
+
+    @RequestMapping(value = "/company", method = RequestMethod.GET)
+    public ModelAndView showForm() {
+        return new ModelAndView("companyHome", "company", new Company());
+    }
+
+    @RequestMapping(value = "/company/{Id}", produces = { "application/json", "application/xml" }, method = RequestMethod.GET)
+    public @ResponseBody Company getCompanyById(@PathVariable final long Id) {
+        return companyMap.get(Id);
+    }
+
+    @RequestMapping(value = "/addCompany", method = RequestMethod.POST)
+    public String submit(@ModelAttribute("company") final Company company, final BindingResult result, final ModelMap model) {
+        if (result.hasErrors()) {
+            return "error";
+        }
+        model.addAttribute("name", company.getName());
+        model.addAttribute("id", company.getId());
+
+        companyMap.put(company.getId(), company);
+
+        return "companyView";
+    }
+
+    @RequestMapping(value = "/companyEmployee/{company}/employeeData/{employee}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<Map<String, String>> getEmployeeDataFromCompany(@MatrixVariable(pathVar = "employee") final Map<String, String> matrixVars) {
+        return new ResponseEntity<>(matrixVars, HttpStatus.OK);
+    }
+
+    @RequestMapping(value = "/companyData/{company}/employeeData/{employee}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<Map<String, String>> getCompanyName(@MatrixVariable(value = "name", pathVar = "company") final String name) {
+        final Map<String, String> result = new HashMap<String, String>();
+        result.put("name", name);
+        return new ResponseEntity<>(result, HttpStatus.OK);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/EmployeeController.java

@@ -0,0 +1,112 @@
+package com.baeldung.web.controller;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.ModelMap;
+import org.springframework.validation.BindingResult;
+import org.springframework.web.bind.annotation.MatrixVariable;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.bind.annotation.SessionAttributes;
+import org.springframework.web.servlet.ModelAndView;
+
+import com.baeldung.model.Employee;
+
+@SessionAttributes("employees")
+@Controller
+public class EmployeeController {
+
+    Map<Long, Employee> employeeMap = new HashMap<>();
+
+    @ModelAttribute("employees")
+    public void initEmployees() {
+        employeeMap.put(1L, new Employee(1L, "John", "223334411", "rh"));
+        employeeMap.put(2L, new Employee(2L, "Peter", "22001543", "informatics"));
+        employeeMap.put(3L, new Employee(3L, "Mike", "223334411", "admin"));
+    }
+
+    @RequestMapping(value = "/employee", method = RequestMethod.GET)
+    public ModelAndView showForm() {
+        return new ModelAndView("employeeHome", "employee", new Employee());
+    }
+
+    @RequestMapping(value = "/employee/{Id}", produces = { "application/json", "application/xml" }, method = RequestMethod.GET)
+    public @ResponseBody Employee getEmployeeById(@PathVariable final long Id) {
+        return employeeMap.get(Id);
+    }
+    
+    @RequestMapping(value = "/addEmployee", method = RequestMethod.POST)
+    public String submit(@ModelAttribute("employee") final Employee employee, final BindingResult result, final ModelMap model) {
+        if (result.hasErrors()) {
+            return "error";
+        }
+        model.addAttribute("name", employee.getName());
+        model.addAttribute("contactNumber", employee.getContactNumber());
+        model.addAttribute("workingArea", employee.getWorkingArea());
+        model.addAttribute("id", employee.getId());
+
+        employeeMap.put(employee.getId(), employee);
+
+        return "employeeView";
+    }
+
+    @RequestMapping(value = "/employees/{name}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<List<Employee>> getEmployeeByNameAndBeginContactNumber(@PathVariable final String name, @MatrixVariable final String beginContactNumber) {
+        final List<Employee> employeesList = new ArrayList<Employee>();
+        for (final Map.Entry<Long, Employee> employeeEntry : employeeMap.entrySet()) {
+            final Employee employee = employeeEntry.getValue();
+            if (employee.getName().equalsIgnoreCase(name) && employee.getContactNumber().startsWith(beginContactNumber)) {
+                employeesList.add(employee);
+            }
+        }
+        return new ResponseEntity<>(employeesList, HttpStatus.OK);
+    }
+
+    @RequestMapping(value = "/employeesContacts/{contactNumber}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<List<Employee>> getEmployeeBycontactNumber(@MatrixVariable(required = true) final String contactNumber) {
+        final List<Employee> employeesList = new ArrayList<Employee>();
+        for (final Map.Entry<Long, Employee> employeeEntry : employeeMap.entrySet()) {
+            final Employee employee = employeeEntry.getValue();
+            if (employee.getContactNumber().equalsIgnoreCase(contactNumber)) {
+                employeesList.add(employee);
+            }
+        }
+        return new ResponseEntity<>(employeesList, HttpStatus.OK);
+    }
+
+    @RequestMapping(value = "employeeData/{employee}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<Map<String, String>> getEmployeeData(@MatrixVariable final Map<String, String> matrixVars) {
+        return new ResponseEntity<>(matrixVars, HttpStatus.OK);
+    }
+
+    @RequestMapping(value = "employeeArea/{workingArea}", method = RequestMethod.GET)
+    @ResponseBody
+    public ResponseEntity<List<Employee>> getEmployeeByWorkingArea(@MatrixVariable final Map<String, LinkedList<String>> matrixVars) {
+        final List<Employee> employeesList = new ArrayList<Employee>();
+        final LinkedList<String> workingArea = matrixVars.get("workingArea");
+        for (final Map.Entry<Long, Employee> employeeEntry : employeeMap.entrySet()) {
+            final Employee employee = employeeEntry.getValue();
+            for (final String area : workingArea) {
+                if (employee.getWorkingArea().equalsIgnoreCase(area)) {
+                    employeesList.add(employee);
+                    break;
+                }
+            }
+        }
+        return new ResponseEntity<>(employeesList, HttpStatus.OK);
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/ExcelController.java

@@ -0,0 +1,63 @@
+package com.baeldung.web.controller;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.multipart.MultipartFile;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import com.baeldung.excel.*;
+import java.util.Map;
+import java.util.List;
+import javax.annotation.Resource;
+
+@Controller
+public class ExcelController {
+
+    private String fileLocation;
+
+    @Resource(name = "excelPOIHelper")
+    private ExcelPOIHelper excelPOIHelper;
+
+    @RequestMapping(method = RequestMethod.GET, value = "/excelProcessing")
+    public String getExcelProcessingPage() {
+        return "excel";
+    }
+
+    @RequestMapping(method = RequestMethod.POST, value = "/uploadExcelFile")
+    public String uploadFile(Model model, MultipartFile file) throws IOException {
+        InputStream in = file.getInputStream();
+        File currDir = new File(".");
+        String path = currDir.getAbsolutePath();
+        fileLocation = path.substring(0, path.length() - 1) + file.getOriginalFilename();
+        FileOutputStream f = new FileOutputStream(fileLocation);
+        int ch = 0;
+        while ((ch = in.read()) != -1) {
+            f.write(ch);
+        }
+        f.flush();
+        f.close();
+        model.addAttribute("message", "File: " + file.getOriginalFilename() + " has been uploaded successfully!");
+        return "excel";
+    }
+
+    @RequestMapping(method = RequestMethod.GET, value = "/readPOI")
+    public String readPOI(Model model) throws IOException {
+
+        if (fileLocation != null) {
+            if (fileLocation.endsWith(".xlsx") || fileLocation.endsWith(".xls")) {
+                Map<Integer, List<MyCell>> data = excelPOIHelper.readExcel(fileLocation);
+                model.addAttribute("data", data);
+            } else {
+                model.addAttribute("message", "Not a valid excel file!");
+            }
+        } else {
+            model.addAttribute("message", "File missing! Please upload an excel file.");
+        }
+        return "excel";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/FileUploadController.java

@@ -0,0 +1,52 @@
+package com.baeldung.web.controller;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.ModelMap;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.model.FormDataWithFile;
+
+@Controller
+public class FileUploadController {
+
+    @RequestMapping(value = "/fileUpload", method = RequestMethod.GET)
+    public String displayForm() {
+
+        return "fileUploadForm";
+    }
+
+    @RequestMapping(value = "/uploadFile", method = RequestMethod.POST)
+    public String submit(@RequestParam("file") final MultipartFile file, final ModelMap modelMap) {
+
+        modelMap.addAttribute("file", file);
+        return "fileUploadView";
+    }
+
+    @RequestMapping(value = "/uploadMultiFile", method = RequestMethod.POST)
+    public String submit(@RequestParam("files") final MultipartFile[] files, final ModelMap modelMap) {
+
+        modelMap.addAttribute("files", files);
+        return "fileUploadView";
+    }
+
+    @RequestMapping(value = "/uploadFileWithAddtionalData", method = RequestMethod.POST)
+    public String submit(@RequestParam final MultipartFile file, @RequestParam final String name, @RequestParam final String email, final ModelMap modelMap) {
+
+        modelMap.addAttribute("name", name);
+        modelMap.addAttribute("email", email);
+        modelMap.addAttribute("file", file);
+        return "fileUploadView";
+    }
+
+    @RequestMapping(value = "/uploadFileModelAttribute", method = RequestMethod.POST)
+    public String submit(@ModelAttribute final FormDataWithFile formDataWithFile, final ModelMap modelMap) {
+
+        modelMap.addAttribute("formDataWithFile", formDataWithFile);
+        return "fileUploadView";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/GreetController.java

@@ -0,0 +1,59 @@
+package com.baeldung.web.controller;
+
+import com.baeldung.model.Greeting;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.*;
+
+@Controller
+public class GreetController {
+
+    @RequestMapping(value = "/homePage", method = RequestMethod.GET)
+    public String index() {
+        return "index";
+    }
+
+    @RequestMapping(value = "/greet", method = RequestMethod.GET, produces = "application/json")
+    @ResponseBody
+    public Greeting greet() {
+        Greeting greeting = new Greeting();
+        greeting.setId(1);
+        greeting.setMessage("Hello World!!!");
+        return greeting;
+    }
+
+    @RequestMapping(value = "/greetWithPathVariable/{name}", method = RequestMethod.GET, produces = "application/json")
+    @ResponseBody
+    public Greeting greetWithPathVariable(@PathVariable("name") String name) {
+        Greeting greeting = new Greeting();
+        greeting.setId(1);
+        greeting.setMessage("Hello World " + name + "!!!");
+        return greeting;
+    }
+
+    @RequestMapping(value = "/greetWithQueryVariable", method = RequestMethod.GET, produces = "application/json")
+    @ResponseBody
+    public Greeting greetWithQueryVariable(@RequestParam("name") String name) {
+        Greeting greeting = new Greeting();
+        greeting.setId(1);
+        greeting.setMessage("Hello World " + name + "!!!");
+        return greeting;
+    }
+
+    @RequestMapping(value = "/greetWithPost", method = RequestMethod.POST, produces = "application/json")
+    @ResponseBody
+    public Greeting greetWithPost() {
+        Greeting greeting = new Greeting();
+        greeting.setId(1);
+        greeting.setMessage("Hello World!!!");
+        return greeting;
+    }
+
+    @RequestMapping(value = "/greetWithPostAndFormData", method = RequestMethod.POST, produces = "application/json")
+    @ResponseBody
+    public Greeting greetWithPostAndFormData(@RequestParam("id") int id, @RequestParam("name") String name) {
+        Greeting greeting = new Greeting();
+        greeting.setId(id);
+        greeting.setMessage("Hello World " + name + "!!!");
+        return greeting;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/ImageController.java

@@ -0,0 +1,27 @@
+package com.baeldung.web.controller;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import javax.servlet.ServletContext;
+
+import org.apache.commons.io.IOUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@Controller
+public class ImageController {
+
+    @Autowired
+    ServletContext servletContext;
+
+    @RequestMapping(value = "/image-byte-array", method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE)
+    public @ResponseBody byte[] getImageAsByteArray() throws IOException {
+        final InputStream in = servletContext.getResourceAsStream("/WEB-INF/images/image-example.jpg");
+        return IOUtils.toByteArray(in);
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/SampleController.java

@@ -0,0 +1,13 @@
+package com.baeldung.web.controller;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+
+@Controller
+public class SampleController {
+	@GetMapping("/sample")
+    public String showForm() {
+        return "sample";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/SiteController.java

@@ -0,0 +1,30 @@
+package com.baeldung.web.controller;
+
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+
+@RequestMapping("/site")
+public class SiteController {
+
+    @RequestMapping(value = "/{firstValue}/{secondValue}", method = RequestMethod.GET)
+    public String requestWithError(@PathVariable("firstValue") String firstValue,
+                          @PathVariable("secondValue") String secondValue) {
+
+        return firstValue + " - " + secondValue;
+    }
+
+    @RequestMapping(value = "/{firstValue}/{secondValue:.+}", method = RequestMethod.GET)
+    public String requestWithRegex(@PathVariable("firstValue") String firstValue,
+                                   @PathVariable("secondValue") String secondValue) {
+
+        return firstValue + " - " + secondValue;
+    }
+
+    @RequestMapping(value = "/{firstValue}/{secondValue}/", method = RequestMethod.GET)
+    public String requestWithSlash(@PathVariable("firstValue") String firstValue,
+                                   @PathVariable("secondValue") String secondValue) {
+
+        return firstValue + " - " + secondValue;
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/UserController.java

@@ -0,0 +1,32 @@
+package com.baeldung.web.controller;
+
+import com.baeldung.model.User;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller
+@RequestMapping("/")
+public class UserController {
+
+    @GetMapping("/")
+    public String showForm(final Model model) {
+        final User user = new User();
+        user.setFirstname("John");
+        user.setLastname("Roy");
+        user.setEmailId("John.Roy@gmail.com");
+        model.addAttribute("user", user);
+        return "index";
+    }
+
+    @PostMapping("/processForm")
+    public String processForm(@ModelAttribute(value = "user") final User user, final Model model) {
+        // Insert User into DB
+        model.addAttribute("name", user.getFirstname() + " " + user.getLastname());
+        return "hello";
+    }
+
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/WebsocketSendToUserController.java

@@ -0,0 +1,30 @@
+package com.baeldung.web.controller;
+
+import java.security.Principal;
+import java.util.Map;
+
+import org.springframework.messaging.handler.annotation.MessageExceptionHandler;
+import org.springframework.messaging.handler.annotation.MessageMapping;
+import org.springframework.messaging.handler.annotation.Payload;
+import org.springframework.messaging.simp.annotation.SendToUser;
+import org.springframework.stereotype.Controller;
+
+import com.google.gson.Gson;
+
+@Controller
+public class WebsocketSendToUserController {
+
+    private Gson gson = new Gson();
+
+    @MessageMapping("/message")
+    @SendToUser("/queue/reply")
+    public String processMessageFromClient(@Payload String message, Principal principal) throws Exception {
+        return gson.fromJson(message, Map.class).get("name").toString();
+    }
+
+    @MessageExceptionHandler
+    @SendToUser("/queue/errors")
+    public String handleException(Throwable exception) {
+        return exception.getMessage();
+    }
+}

spring-mvc-java/src/main/java/com/baeldung/web/controller/message/MessageController.java

@@ -0,0 +1,24 @@
+package com.baeldung.web.controller.message;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+
+@Controller
+@RequestMapping("/message")
+public class MessageController {
+
+    @RequestMapping(value = "/showForm", method = RequestMethod.GET)
+    public String showForm() {
+        return "message";
+    }
+
+    @RequestMapping(value = "/processForm", method = RequestMethod.POST)
+    public String processForm(@RequestParam("message") final String message, final Model model) {
+        model.addAttribute("message", message);
+        return "message";
+    }
+
+}