Merge branch 'master' of https://github.com/eugenp/tutorials into BAEL-16767

2019-09-07 19:45:49 +05:30
parent f7957e2fa8 b3323d5f22
commit 3166e2eee5
236 changed files with 5263 additions and 3458 deletions
@@ -0,0 +1,70 @@
+package com.baeldung.bucketsort;
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.List;
+
+public class IntegerBucketSorter implements Sorter<Integer> {
+
+    private final Comparator<Integer> comparator;
+
+    public IntegerBucketSorter(Comparator<Integer> comparator) {
+        this.comparator = comparator;
+    }
+
+    public IntegerBucketSorter() {
+        comparator = Comparator.naturalOrder();
+    }
+
+    public List<Integer> sort(List<Integer> arrayToSort) {
+
+        List<List<Integer>> buckets = splitIntoUnsortedBuckets(arrayToSort);
+
+        for(List<Integer> bucket  : buckets){
+            bucket.sort(comparator);
+        }
+
+        return concatenateSortedBuckets(buckets);
+    }
+
+    private List<Integer> concatenateSortedBuckets(List<List<Integer>> buckets){
+        List<Integer> sortedArray = new ArrayList<>();
+        int index = 0;
+        for(List<Integer> bucket : buckets){
+            for(int number : bucket){
+                sortedArray.add(index++, number);
+            }
+        }
+        return sortedArray;
+    }
+
+    private List<List<Integer>> splitIntoUnsortedBuckets(List<Integer> initialList){
+
+        final int[] codes = createHashes(initialList);
+
+        List<List<Integer>> buckets = new ArrayList<>(codes[1]);
+        for(int i = 0; i < codes[1]; i++) buckets.add(new ArrayList<>());
+
+        //distribute the data
+        for (int i : initialList) {
+            buckets.get(hash(i, codes)).add(i);
+        }
+        return buckets;
+
+    }
+
+    private int[] createHashes(List<Integer> input){
+        int m = input.get(0);
+        for (int i = 1; i < input.size(); i++) {
+            if (m < input.get(i)) {
+                m = input.get(i);
+            }
+        }
+        return new int[]{m, (int) Math.sqrt(input.size())};
+    }
+
+    private static int hash(int i, int[] code) {
+        return (int) ((double) i / code[0] * (code[1] - 1));
+    }
+
+}
@@ -0,0 +1,8 @@
+package com.baeldung.bucketsort;
+
+import java.util.List;
+
+public interface Sorter<T> {
+
+    List<T> sort(List<T> arrayToSort);
+}
@@ -0,0 +1,33 @@
+package com.baeldung.bucketsort;
+
+import com.baeldung.bucketsort.IntegerBucketSorter;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+
+public class IntegerBucketSorterUnitTest {
+
+    private IntegerBucketSorter sorter;
+
+    @Before
+    public void setUp() throws Exception {
+        sorter = new IntegerBucketSorter();
+    }
+
+    @Test
+    public void givenUnsortedList_whenSortedUsingBucketSorter_checkSortingCorrect() {
+
+        List<Integer> unsorted = Arrays.asList(80,50,60,30,20,10,70,0,40,500,600,602,200,15);
+        List<Integer> expected = Arrays.asList(0,10,15,20,30,40,50,60,70,80,200,500,600,602);
+
+        List<Integer> actual = sorter.sort(unsorted);
+
+        assertEquals(expected, actual);
+
+
+    }
+}
@@ -0,0 +1,3 @@
+## Relevant Articles:
+
+- [Building Java Applications with Bazel](https://www.baeldung.com/bazel-build-tool)
@@ -48,6 +48,11 @@
            <version>${spock-core.version}</version>
            <scope>test</scope>
        </dependency>
+        <dependency>
+            <groupId>com.github.groovy-wslite</groupId>
+            <artifactId>groovy-wslite</artifactId>
+            <version>${groovy-wslite.version}</version>
+        </dependency>
    </dependencies>

    <build>
@@ -175,6 +180,7 @@
        <junit.platform.version>1.0.0</junit.platform.version>
        <hsqldb.version>2.4.0</hsqldb.version>
        <spock-core.version>1.1-groovy-2.4</spock-core.version>
+        <groovy-wslite.version>1.1.3</groovy-wslite.version>        
        <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
        <logback.version>1.2.3</logback.version>
        <groovy.version>2.5.7</groovy.version>
@@ -0,0 +1,152 @@
+package com.baeldung.webservice
+
+import groovy.json.JsonSlurper
+import wslite.rest.ContentType
+import wslite.rest.RESTClient
+import wslite.rest.RESTClientException
+import wslite.soap.SOAPClient
+import wslite.soap.SOAPMessageBuilder
+import wslite.http.auth.HTTPBasicAuthorization
+import org.junit.Test
+
+class WebserviceUnitTest extends GroovyTestCase {
+
+    JsonSlurper jsonSlurper = new JsonSlurper()
+
+    static RESTClient client = new RESTClient("https://postman-echo.com")
+    
+    static {
+        client.defaultAcceptHeader = ContentType.JSON
+        client.httpClient.sslTrustAllCerts = true
+    }
+
+    void test_whenSendingGet_thenRespose200() {
+        def postmanGet = new URL('https://postman-echo.com/get')
+        def getConnection = postmanGet.openConnection()
+        getConnection.requestMethod = 'GET'
+        assert getConnection.responseCode == 200
+        if (getConnection.responseCode == 200) {
+            assert jsonSlurper.parseText(getConnection.content.text)?.headers?.host == "postman-echo.com"
+        }
+    }
+
+    void test_whenSendingPost_thenRespose200() {
+        def postmanPost = new URL('https://postman-echo.com/post')
+        def query = "q=This is post request form parameter."
+        def postConnection = postmanPost.openConnection()
+        postConnection.requestMethod = 'POST'
+        assert postConnection.responseCode == 200
+    }
+    
+    void test_whenSendingPostWithParams_thenRespose200() {
+        def postmanPost = new URL('https://postman-echo.com/post')
+        def form = "param1=This is request parameter."
+        def postConnection = postmanPost.openConnection()
+        postConnection.requestMethod = 'POST'
+        postConnection.doOutput = true
+        def text
+        postConnection.with {
+            outputStream.withWriter { outputStreamWriter ->
+                outputStreamWriter << form
+            }
+            text = content.text
+        }
+        assert postConnection.responseCode == 200
+        assert jsonSlurper.parseText(text)?.json.param1 == "This is request parameter."
+    }
+    
+    void test_whenReadingRSS_thenReceiveFeed() {
+        def rssFeed = new XmlParser().parse("https://news.google.com/rss?hl=en-US&gl=US&ceid=US:en")
+        def stories = []
+        (0..4).each {
+            def item = rssFeed.channel.item.get(it)
+            stories << item.title.text()
+        }
+        assert stories.size() == 5
+    }
+
+    void test_whenReadingAtom_thenReceiveFeed() {
+        def atomFeed = new XmlParser().parse("https://news.google.com/atom?hl=en-US&gl=US&ceid=US:en")
+        def stories = []
+        (0..4).each {
+            def entry = atomFeed.entry.get(it)
+            stories << entry.title.text()
+        }
+        assert stories.size() == 5
+    }
+    
+    void test_whenConsumingSoap_thenReceiveResponse() {
+        def url = "http://www.dataaccess.com/webservicesserver/numberconversion.wso"
+        def soapClient = new SOAPClient(url)
+        def message = new SOAPMessageBuilder().build({
+            body {
+                NumberToWords(xmlns: "http://www.dataaccess.com/webservicesserver/") {
+                    ubiNum(1234)
+                }
+            }
+        })
+        def response = soapClient.send(message.toString());
+        def words = response.NumberToWordsResponse
+        assert words == "one thousand two hundred and thirty four "
+    }
+
+    void test_whenConsumingRestGet_thenReceiveResponse() {
+        def path = "/get"
+        def response
+        try {
+            response = client.get(path: path)
+            assert response.statusCode == 200
+            assert response.json?.headers?.host == "postman-echo.com"
+        } catch (RESTClientException e) {
+            assert e?.response?.statusCode != 200
+        }
+    }
+
+    void test_whenConsumingRestPost_thenReceiveResponse() {
+        def path = "/post"
+        def params = ["foo":1,"bar":2]
+        def response
+        try {
+            response = client.post(path: path) {
+                type ContentType.JSON
+                json params
+            }
+            assert response.json?.data == params
+        } catch (RESTClientException e) {
+            e.printStackTrace()
+            assert e?.response?.statusCode != 200
+        }
+    }
+
+    void test_whenBasicAuthentication_thenReceive200() {
+        def path = "/basic-auth"
+        def response
+        try {
+            client.authorization = new HTTPBasicAuthorization("postman", "password")
+            response = client.get(path: path)
+            assert response.statusCode == 200
+            assert response.json?.authenticated == true
+        } catch (RESTClientException e) {
+            e.printStackTrace()
+            assert e?.response?.statusCode != 200
+        }
+    }
+
+    void test_whenOAuth_thenReceive200() {
+        RESTClient oAuthClient = new RESTClient("https://postman-echo.com")
+        oAuthClient.defaultAcceptHeader = ContentType.JSON
+        oAuthClient.httpClient.sslTrustAllCerts = true
+
+        def path = "/oauth1"
+        def params = [oauth_consumer_key: "RKCGzna7bv9YD57c", oauth_signature_method: "HMAC-SHA1", oauth_timestamp:1567089944, oauth_nonce: "URT7v4", oauth_version: 1.0, oauth_signature: 'RGgR/ktDmclkM0ISWaFzebtlO0A=']
+        def response
+        try {
+            response = oAuthClient.get(path: path, query: params)
+            assert response.statusCode == 200
+            assert response.statusMessage == "OK"
+            assert response.json.status == "pass"
+        } catch (RESTClientException e) {
+            assert e?.response?.statusCode != 200
+        }
+    }
+}
@@ -1,4 +1,4 @@
-package com.baeldung.java8;
+package com.baeldung.java_8_features.groupingby;

 import com.baeldung.java_8_features.groupingby.BlogPost;
 import com.baeldung.java_8_features.groupingby.BlogPostType;
@@ -0,0 +1,40 @@
+package com.baeldung.java.list;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+public class RemoveFromList {
+
+        public static void main(String[] args) {
+                List<String> sports = new ArrayList<>();
+                sports.add("Football");
+                sports.add("Basketball");
+                sports.add("Baseball");
+                sports.add("Boxing");
+                sports.add("Cycling");
+
+                System.out.println("List before removing:  " + sports);
+
+                // Remove with index
+                sports.remove(1);
+
+                // Remove with an element
+                sports.remove("Baseball");
+
+                // Iterator remove method
+                Iterator<String> iterator = sports.iterator();
+                while (iterator.hasNext()) {
+                        if (iterator.next().equals("Boxing")) {
+                                iterator.remove();
+                                break;
+                        }
+                }
+
+                // ArrayList removeIf method (Java 8)
+                sports.removeIf(p -> p.equals("Cycling"));
+
+                System.out.println("List after removing:  " + sports);
+        }
+
+}
@@ -1,4 +1,4 @@
-package com.baeldung.java8;
+package com.baeldung.concurrent.executorservice;

 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -0,0 +1,3 @@
+# Intellij
+.idea/
+*.iml
@@ -0,0 +1,279 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>core-java-io-2</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>core-java-io-2</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-java</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../parent-java</relativePath>
+    </parent>
+
+    <dependencies>
+        <!-- utils -->
+        <dependency>
+            <groupId>net.sourceforge.collections</groupId>
+            <artifactId>collections-generic</artifactId>
+            <version>${collections-generic.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-collections4</artifactId>
+            <version>${commons-collections4.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <version>${commons-io.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>${commons-lang3.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-math3</artifactId>
+            <version>${commons-math3.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.decimal4j</groupId>
+            <artifactId>decimal4j</artifactId>
+            <version>${decimal4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.bouncycastle</groupId>
+            <artifactId>bcprov-jdk15on</artifactId>
+            <version>${bouncycastle.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.unix4j</groupId>
+            <artifactId>unix4j-command</artifactId>
+            <version>${unix4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.googlecode.grep4j</groupId>
+            <artifactId>grep4j</artifactId>
+            <version>${grep4j.version}</version>
+        </dependency>
+        <!-- web -->
+        <!-- marshalling -->
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+        <!-- logging -->
+        <dependency>
+            <groupId>log4j</groupId>
+            <artifactId>log4j</artifactId>
+            <version>${log4j.version}</version>
+        </dependency>
+        <dependency> <!-- needed to bridge to slf4j for projects that use the log4j APIs directly -->
+            <groupId>org.slf4j</groupId>
+            <artifactId>log4j-over-slf4j</artifactId>
+            <version>${org.slf4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>${lombok.version}</version>
+            <scope>provided</scope>
+        </dependency>
+        <!-- test scoped -->
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.jayway.awaitility</groupId>
+            <artifactId>awaitility</artifactId>
+            <version>${avaitility.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>${commons-codec.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.javamoney</groupId>
+            <artifactId>moneta</artifactId>
+            <version>${moneta.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.owasp.esapi</groupId>
+            <artifactId>esapi</artifactId>
+            <version>${esapi.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.sun.messaging.mq</groupId>
+            <artifactId>fscontext</artifactId>
+            <version>${fscontext.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.codepoetics</groupId>
+            <artifactId>protonpack</artifactId>
+            <version>${protonpack.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>one.util</groupId>
+            <artifactId>streamex</artifactId>
+            <version>${streamex.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.vavr</groupId>
+            <artifactId>vavr</artifactId>
+            <version>${vavr.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>${jmh-core.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh-generator-annprocess.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hsqldb</groupId>
+            <artifactId>hsqldb</artifactId>
+            <version>${hsqldb.version}</version>
+            <scope>runtime</scope>
+        </dependency>
+        <!-- https://mvnrepository.com/artifact/org.asynchttpclient/async-http-client -->
+        <dependency>
+            <groupId>org.asynchttpclient</groupId>
+            <artifactId>async-http-client</artifactId>
+            <version>${async-http-client.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.opencsv</groupId>
+            <artifactId>opencsv</artifactId>
+            <version>${opencsv.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <!-- Mime Type Resolution Libraries -->
+        <dependency>
+            <groupId>org.apache.tika</groupId>
+            <artifactId>tika-core</artifactId>
+            <version>${tika.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>net.sf.jmimemagic</groupId>
+            <artifactId>jmimemagic</artifactId>
+            <version>${jmime-magic.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <finalName>core-java-io-2</finalName>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+        <plugins>
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>exec-maven-plugin</artifactId>
+                <version>${exec-maven-plugin.version}</version>
+                <configuration>
+                    <executable>java</executable>
+                    <mainClass>com.baeldung.outofmemoryerror.OutOfMemoryGCLimitExceed</mainClass>
+                    <arguments>
+                        <argument>-Xmx300m</argument>
+                        <argument>-XX:+UseParallelGC</argument>
+                        <argument>-classpath</argument>
+                        <classpath />
+                        <argument>com.baeldung.outofmemoryerror.OutOfMemoryGCLimitExceed</argument>
+                    </arguments>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>${maven-javadoc-plugin.version}</version>
+                <configuration>
+                    <source>${maven.compiler.source}</source>
+                    <target>${maven.compiler.target}</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+    <profiles>
+        <profile>
+            <id>integration</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.codehaus.mojo</groupId>
+                        <artifactId>exec-maven-plugin</artifactId>
+
+                        <executions>
+                            <execution>
+                                <id>run-benchmarks</id>
+                                <!-- <phase>integration-test</phase> -->
+                                <phase>none</phase>
+                                <goals>
+                                    <goal>exec</goal>
+                                </goals>
+                                <configuration>
+                                    <classpathScope>test</classpathScope>
+                                    <executable>java</executable>
+                                    <arguments>
+                                        <argument>-classpath</argument>
+                                        <classpath />
+                                        <argument>org.openjdk.jmh.Main</argument>
+                                        <argument>.*</argument>
+                                    </arguments>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
+
+    <properties>
+
+        <!-- util -->
+        <bouncycastle.version>1.55</bouncycastle.version>
+        <commons-codec.version>1.10</commons-codec.version>
+        <commons-math3.version>3.6.1</commons-math3.version>
+        <decimal4j.version>1.0.3</decimal4j.version>
+        <commons-collections4.version>4.1</commons-collections4.version>
+        <collections-generic.version>4.01</collections-generic.version>
+        <unix4j.version>0.4</unix4j.version>
+        <grep4j.version>1.8.7</grep4j.version>
+        <fscontext.version>4.6-b01</fscontext.version>
+        <protonpack.version>1.13</protonpack.version>
+        <streamex.version>0.6.5</streamex.version>
+        <vavr.version>0.9.0</vavr.version>
+        <opencsv.version>4.1</opencsv.version>
+        <!-- testing -->
+        <assertj.version>3.6.1</assertj.version>
+        <avaitility.version>1.7.0</avaitility.version>
+
+        <!-- maven plugins -->
+        <maven-javadoc-plugin.version>3.0.0-M1</maven-javadoc-plugin.version>
+        <hsqldb.version>2.4.0</hsqldb.version>
+        <esapi.version>2.1.0.1</esapi.version>
+        <jmh-generator-annprocess.version>1.19</jmh-generator-annprocess.version>
+        <async-http-client.version>2.4.5</async-http-client.version>
+        <!-- Mime Type Libraries -->
+        <tika.version>1.18</tika.version>
+        <jmime-magic.version>0.1.5</jmime-magic.version>
+    </properties>
+
+</project>
@@ -0,0 +1,57 @@
+package com.baeldung.filereader;
+
+import java.io.*;
+
+public class FileReaderExample {
+
+    public static String readAllCharactersOneByOne(Reader reader) throws IOException {
+        StringBuilder content = new StringBuilder();
+        int nextChar;
+        while ((nextChar = reader.read()) != -1) {
+            content.append((char) nextChar);
+        }
+        return String.valueOf(content);
+    }
+
+    public static String readMultipleCharacters(Reader reader, int length) throws IOException {
+        char[] buffer = new char[length];
+        int charactersRead = reader.read(buffer, 0, length);
+
+
+        if (charactersRead != -1) {
+            return new String(buffer, 0, charactersRead);
+        } else {
+            return "";
+        }
+    }
+
+    public static String readFile(String path) {
+        FileReader fileReader = null;
+        try {
+            fileReader = new FileReader(path);
+            return readAllCharactersOneByOne(fileReader);
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            if (fileReader != null) {
+                try {
+                    fileReader.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+        return null;
+    }
+
+    public static String readFileUsingTryWithResources(String path) {
+        try (FileReader fileReader = new FileReader(path)) {
+            return readAllCharactersOneByOne(fileReader);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+
+}
@@ -0,0 +1,50 @@
+package com.baeldung.filereader;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+
+public class FileReaderExampleUnitTest {
+
+
+    private static final String FILE_PATH = "src/test/resources/HelloWorld.txt";
+
+
+    @Test
+    public void givenFileReader_whenReadAllCharacters_thenReturnsContent() throws IOException {
+        String expectedText = "Hello, World!";
+        File file = new File(FILE_PATH);
+        try (FileReader fileReader = new FileReader(file)) {
+            String content = FileReaderExample.readAllCharactersOneByOne(fileReader);
+            Assert.assertEquals(expectedText, content);
+        }
+    }
+
+    @Test
+    public void givenFileReader_whenReadMultipleCharacters_thenReturnsContent() throws IOException {
+        String expectedText = "Hello";
+        File file = new File(FILE_PATH);
+        try (FileReader fileReader = new FileReader(file)) {
+            String content = FileReaderExample.readMultipleCharacters(fileReader, 5);
+            Assert.assertEquals(expectedText, content);
+        }
+    }
+
+    @Test
+    public void whenReadFile_thenReturnsContent() {
+        String expectedText = "Hello, World!";
+        String content = FileReaderExample.readFile(FILE_PATH);
+        Assert.assertEquals(expectedText, content);
+    }
+
+    @Test
+    public void whenReadFileUsingTryWithResources_thenReturnsContent() {
+        String expectedText = "Hello, World!";
+        String content = FileReaderExample.readFileUsingTryWithResources(FILE_PATH);
+        Assert.assertEquals(expectedText, content);
+    }
+
+}
@@ -0,0 +1 @@
+Hello, World!
@@ -207,6 +207,21 @@
                    <target>${maven.compiler.target}</target>
                </configuration>
            </plugin>
+            
+            <plugin>
+                <!-- Build an executable JAR -->
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <version>${maven-jar-plugin.version}</version>
+                <configuration>
+                    <archive>
+                        <manifest>
+                            <addClasspath>true</addClasspath>
+                            <mainClass>com.baeldung.resource.MyResourceLoader</mainClass>
+                        </manifest>
+                    </archive>
+                </configuration>
+            </plugin>
        </plugins>
    </build>

@@ -274,6 +289,8 @@
        <!-- Mime Type Libraries -->
        <tika.version>1.18</tika.version>
        <jmime-magic.version>0.1.5</jmime-magic.version>
+        <maven-jar-plugin.version>3.1.0</maven-jar-plugin.version>
+
    </properties>

 </project>
@@ -0,0 +1,42 @@
+package com.baeldung.resource;
+
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.stream.Collectors;
+
+public class MyResourceLoader {
+
+    private void loadFileWithReader() throws IOException {
+
+        try (FileReader fileReader = new FileReader("src/main/resources/input.txt");
+             BufferedReader reader = new BufferedReader(fileReader)) {
+            String contents = reader.lines()
+                .collect(Collectors.joining(System.lineSeparator()));
+            System.out.println(contents);
+        }
+
+    }
+
+    private void loadFileAsResource() throws IOException {
+
+        try (InputStream inputStream = getClass().getResourceAsStream("/input.txt");
+             BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream))) {
+            String contents = reader.lines()
+                .collect(Collectors.joining(System.lineSeparator()));
+            System.out.println(contents);
+        }
+    }
+
+    public static void main(String[] args) throws IOException {
+
+        MyResourceLoader resourceLoader = new MyResourceLoader();
+
+        resourceLoader.loadFileAsResource();
+        resourceLoader.loadFileWithReader();
+
+    }
+
+}
@@ -0,0 +1,25 @@
+*.class
+
+0.*
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+.resourceCache
+
+# Packaged files #
+*.jar
+*.war
+*.ear
+
+# Files generated by integration tests
+backup-pom.xml
+/bin/
+/temp
+
+#IntelliJ specific
+.idea/
+*.iml
@@ -0,0 +1,5 @@
+=========
+
+## Core Java Lang Cookbooks and Examples
+
+### Relevant Articles: 
@@ -0,0 +1,33 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung</groupId>
+    <artifactId>core-java-lang-2</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>core-java-lang-2</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-java</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../parent-java</relativePath>
+    </parent>
+
+    <dependencies>
+    </dependencies>
+
+    <build>
+        <finalName>core-java-lang-2</finalName>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+    </build>
+
+    <properties>
+    </properties>
+
+</project>
@@ -0,0 +1,12 @@
+package com.baeldung.commandlinearguments;
+
+public class CliExample {
+
+    public static void main(String[] args) {
+        System.out.println("Argument count: " + args.length);
+        for (int i = 0; i < args.length; i++) {
+            System.out.println("Argument " + i + ": " + args[i]);
+        }
+    }
+
+}
@@ -0,0 +1,12 @@
+package com.baeldung.commandlinearguments;
+
+public class CliExampleWithVarargs {
+
+    public static void main(String... args) {
+        System.out.println("Argument count: " + args.length);
+        for (int i = 0; i < args.length; i++) {
+            System.out.println("Argument " + i + ": " + args[i]);
+        }
+    }
+
+}
@@ -14,6 +14,19 @@
        <relativePath>../../parent-java</relativePath>
    </parent>

+	<dependencies>
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+			<version>${h2.version}</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+    <properties>
+        <h2.version>1.4.199</h2.version>
+    </properties>
+    
    <build>
        <finalName>core-java-lang-oop-2</finalName>
        <resources>
@@ -0,0 +1,31 @@
+package com.baeldung.accessmodifiers.publicmodifier;
+
+import java.util.AbstractList;
+import java.util.Arrays;
+
+public class ListOfThree<E> extends AbstractList<E> {
+
+    private static final int LENGTH = 3;
+    private Object[] elements;
+    
+    public ListOfThree(E[] data) {
+        if(data == null 
+            || data.length != LENGTH)
+            throw new IllegalArgumentException();
+        
+        this.elements = Arrays.copyOf(data, data.length); //shallow copy
+        
+    }
+    
+    @Override
+    @SuppressWarnings("unchecked")
+    public E get(int index) {      
+        return (E)elements[index];
+    }
+    
+    @Override
+    public int size() {
+        return LENGTH;
+    }
+
+}
@@ -0,0 +1,7 @@
+package com.baeldung.accessmodifiers.publicmodifier;
+
+public class SpecialCharacters {
+
+    public static final String SLASH = "/";
+    
+}
@@ -0,0 +1,67 @@
+package com.baeldung.accessmodifiers.publicmodifier;
+
+import java.math.BigDecimal;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.Date;
+
+public class Student {
+
+    private StudentGrade grade; //new data representation
+//    private int grade; //old data representation
+    private String name;   
+    private int age;
+    
+    public void setGrade(int grade) {        
+        this.grade = new StudentGrade(grade);
+    }
+
+    public int getGrade() {
+        return this.grade.getGrade().intValue(); //int is returned for backward compatibility
+    }
+    
+    public Connection getConnection() throws SQLException {
+        
+        final String URL = "jdbc:h2:~/test";
+        return DriverManager.getConnection(URL, "sa", "");
+
+    }
+        
+    public void setAge(int age) {
+        if (age < 0 || age > 150) {
+            throw new IllegalArgumentException();
+        }
+        
+        this.age = age;
+    }
+
+    public int getAge() {
+        return age;
+    }
+    
+    @Override
+    public String toString() {
+        return this.name;
+    }
+
+    private class StudentGrade {
+        private BigDecimal grade = BigDecimal.ZERO;
+        private Date updatedAt;
+        
+        public StudentGrade(int grade) {
+            this.grade = new BigDecimal(grade);
+            this.updatedAt = new Date();
+        }
+        
+        public BigDecimal getGrade() {
+            return grade;
+        }
+        
+        public Date getDate() {
+            return updatedAt;
+        }
+        
+     }
+    
+}
@@ -0,0 +1,30 @@
+package com.baeldung.copyconstructor;
+
+import java.util.Date;
+
+public class Employee {
+
+    protected int id;
+    protected String name;
+    protected Date startDate;
+
+    public Employee(int id, String name, Date startDate) {
+        this.id = id;
+        this.name = name;
+        this.startDate = startDate;
+    }
+
+    public Employee(Employee employee) {
+        this.id = employee.id;
+        this.name = employee.name;
+        this.startDate = new Date(employee.startDate.getTime());
+    }
+
+    Date getStartDate() {
+        return startDate;
+    }
+
+    public Employee copy() {
+        return new Employee(this);
+    }
+}
@@ -0,0 +1,31 @@
+package com.baeldung.copyconstructor;
+
+import java.util.Date;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class Manager extends Employee {
+
+    private List<Employee> directReports;
+
+    public Manager(int id, String name, Date startDate, List<Employee> directReports) {
+        super(id, name, startDate);
+        this.directReports = directReports;
+    }
+
+    public Manager(Manager manager) {
+        super(manager.id, manager.name, manager.startDate);
+        this.directReports = manager.directReports.stream()
+          .collect(Collectors.toList());
+    }
+
+    @Override
+    public Employee copy() {
+        return new Manager(this);
+    }
+
+    List<Employee> getDirectReport() {
+        return this.directReports;
+    }
+
+}
@@ -3,12 +3,12 @@ package com.baeldung.core.modifiers;
 public class Employee {

    private String privateId;
-    public String name;
+    private String name;
    private boolean manager;

    public Employee(String id, String name) {
-        changeId(id);
-        this.name = name;
+        setPrivateId(id);
+        setName(name);
    }

    private Employee(String id, String name, boolean managerAttribute) {
@@ -17,7 +17,7 @@ public class Employee {
        this.privateId = id + "_ID-MANAGER";
    }

-    public void changeId(String customId) {
+    public void setPrivateId(String customId) {
        if (customId.endsWith("_ID")) {
            this.privateId = customId;
        } else {
@@ -25,7 +25,7 @@ public class Employee {
        }
    }

-    public String getId() {
+    public String getPrivateId() {
        return privateId;
    }

@@ -43,6 +43,15 @@ public class Employee {
        this.manager = manager;
    }

+    
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+    
    public static Employee buildManager(String id, String name) {
        return new Employee(id, name, true);
    }
@@ -4,7 +4,7 @@ public class ExampleClass {

    public static void main(String[] args) {
        Employee employee = new Employee("Bob","ABC123");
-        employee.changeId("BCD234");
-        System.out.println(employee.getId());
+        employee.setPrivateId("BCD234");
+        System.out.println(employee.getPrivateId());
    }
 }
@@ -0,0 +1,93 @@
+package com.baeldung.accessmodifiers;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInstance;
+import org.junit.jupiter.api.TestInstance.Lifecycle;
+import com.baeldung.accessmodifiers.publicmodifier.ListOfThree;
+import com.baeldung.accessmodifiers.publicmodifier.Student;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import java.math.BigDecimal;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+@TestInstance(Lifecycle.PER_CLASS)
+public class PublicAccessModifierUnitTest {
+
+    @Test
+    public void whenUsingBigDecimalIntValueMethod_correspondingIntIsReturned() {
+        assertEquals(0, new BigDecimal(0).intValue()); //instance member
+    }
+    
+    @Test
+    public void whenUsingIntegerMaxValueField_maxPossibleIntValueIsReturned() {
+        assertEquals(2147483647, Integer.MAX_VALUE); //static field
+    }
+    
+    @Test
+    public void whenChangingStudentInternalRepresentation_clientCodeWillNotBreak() {
+        
+        Student student = new Student();
+        student.setGrade(100);
+        
+        assertEquals(100, student.getGrade());
+    }
+    
+    @Test
+    public void whenUsingEntrySet_keyValuePairsAreReturned() {
+        
+        Map<String, String> mapObject = new HashMap<String, String>();
+        mapObject.put("name", "Alex");
+       
+        for(Map.Entry<String, String> entry : mapObject.entrySet()) {
+            assertEquals("name", entry.getKey());
+            assertEquals("Alex", entry.getValue());
+        }
+        
+    }
+    
+    @Test
+    public void whenUsingStringToLowerCase_stringTurnsToLowerCase() {
+        assertEquals("alex", "ALEX".toLowerCase());
+    }
+
+    @Test
+    public void whenParsingStringOne_parseIntReturns1() {
+        assertEquals(1, Integer.parseInt("1"));
+    }
+    
+    @Test
+    public void whenConnectingToH2_connectionInstanceIsReturned() throws SQLException {
+
+        final String url = "jdbc:h2:~/test";
+        Connection conn = DriverManager.getConnection(url, "sa", "");
+        assertNotNull(conn);
+    }
+
+    @Test
+    public void whenCreatingCustomList_concreteAndInheritedMethodsWork() {
+
+        String[] dataSet1 = new String[] {"zero", "one", "two"};
+        
+        List<String> list1 = new ListOfThree<String>(dataSet1);
+        
+        //our implemented methods
+        assertEquals("one", list1.get(1));
+        assertEquals(3, list1.size());
+
+        //inherited implementations
+        assertEquals(1, list1.indexOf("one"));
+        
+        String[] dataSet2 = new String[] {"two", "zero", "one"};
+        List<String> list2 = new ListOfThree<String>(dataSet2);
+        
+        assertTrue(list1.containsAll(list2));
+    }
+    
+}
--- a/Show More
+++ b/Show More