BAEL-2569 Merge branch 'master' of https://github.com/eugenp/tutorials

2019-03-29 23:55:35 +11:00
parent 9f8058a560 49444124ed
commit b45b5cd909
593 changed files with 11668 additions and 4294 deletions
@@ -17,3 +17,4 @@
 - [Java Two Pointer Technique](https://www.baeldung.com/java-two-pointer-technique)
 - [Permutations of an Array in Java](https://www.baeldung.com/java-array-permutations)
 - [Implementing Simple State Machines with Java Enums](https://www.baeldung.com/java-enum-simple-state-machine)
+- [Generate Combinations in Java](https://www.baeldung.com/java-combinations-algorithm)
@@ -0,0 +1,45 @@
+package com.baeldung.algorithms.relativelyprime;
+
+import java.math.BigInteger;
+
+class RelativelyPrime {
+
+    static boolean iterativeRelativelyPrime(int a, int b) {
+        return iterativeGCD(a, b) == 1;
+    }
+
+    static boolean recursiveRelativelyPrime(int a, int b) {
+        return recursiveGCD(a, b) == 1;
+    }
+
+    static boolean bigIntegerRelativelyPrime(int a, int b) {
+        return BigInteger.valueOf(a).gcd(BigInteger.valueOf(b)).equals(BigInteger.ONE);
+    }
+
+    private static int iterativeGCD(int a, int b) {
+        int tmp;
+        while (b != 0) {
+            if (a < b) {
+                tmp = a;
+                a = b;
+                b = tmp;
+            }
+            tmp = b;
+            b = a % b;
+            a = tmp;
+        }
+        return a;
+    }
+
+    private static int recursiveGCD(int a, int b) {
+        if (b == 0) {
+            return a;
+        }
+        if (a < b) {
+            return recursiveGCD(b, a);
+        }
+        return recursiveGCD(b, a % b);
+    }
+
+
+}
@@ -0,0 +1,42 @@
+package com.baeldung.algorithms.reversingtree;
+
+public class TreeNode {
+
+    private int value;
+    private TreeNode rightChild;
+    private TreeNode leftChild;
+
+    public int getValue() {
+        return value;
+    }
+
+    public void setValue(int value) {
+        this.value = value;
+    }
+
+    public TreeNode getRightChild() {
+        return rightChild;
+    }
+
+    public void setRightChild(TreeNode rightChild) {
+        this.rightChild = rightChild;
+    }
+
+    public TreeNode getLeftChild() {
+        return leftChild;
+    }
+
+    public void setLeftChild(TreeNode leftChild) {
+        this.leftChild = leftChild;
+    }
+
+    public TreeNode(int value, TreeNode rightChild, TreeNode leftChild) {
+        this.value = value;
+        this.rightChild = rightChild;
+        this.leftChild = leftChild;
+    }
+
+    public TreeNode(int value) {
+        this.value = value;
+    }
+}
@@ -0,0 +1,68 @@
+package com.baeldung.algorithms.reversingtree;
+
+import java.util.LinkedList;
+
+public class TreeReverser {
+
+    public TreeNode createBinaryTree() {
+
+        TreeNode leaf1 = new TreeNode(3);
+        TreeNode leaf2 = new TreeNode(1);
+        TreeNode leaf3 = new TreeNode(9);
+        TreeNode leaf4 = new TreeNode(6);
+
+        TreeNode nodeLeft = new TreeNode(2, leaf1, leaf2);
+        TreeNode nodeRight = new TreeNode(7, leaf3, leaf4);
+
+        TreeNode root = new TreeNode(4, nodeRight, nodeLeft);
+
+        return root;
+    }
+
+    public void reverseRecursive(TreeNode treeNode) {
+        if (treeNode == null) {
+            return;
+        }
+
+        TreeNode temp = treeNode.getLeftChild();
+        treeNode.setLeftChild(treeNode.getRightChild());
+        treeNode.setRightChild(temp);
+
+        reverseRecursive(treeNode.getLeftChild());
+        reverseRecursive(treeNode.getRightChild());
+    }
+
+    public void reverseIterative(TreeNode treeNode) {
+        LinkedList<TreeNode> queue = new LinkedList<TreeNode>();
+
+        if (treeNode != null) {
+            queue.add(treeNode);
+        }
+
+        while (!queue.isEmpty()) {
+
+            TreeNode node = queue.poll();
+            if (node.getLeftChild() != null)
+                queue.add(node.getLeftChild());
+            if (node.getRightChild() != null)
+                queue.add(node.getRightChild());
+
+            TreeNode temp = node.getLeftChild();
+            node.setLeftChild(node.getRightChild());
+            node.setRightChild(temp);
+        }
+    }
+
+    public String toString(TreeNode root) {
+        if (root == null) {
+            return "";
+        }
+
+        StringBuffer buffer = new StringBuffer(String.valueOf(root.getValue())).append(" ");
+
+        buffer.append(toString(root.getLeftChild()));
+        buffer.append(toString(root.getRightChild()));
+
+        return buffer.toString();
+    }
+}
@@ -0,0 +1,51 @@
+package com.baeldung.algorithms.relativelyprime;
+
+import org.junit.Test;
+
+import static com.baeldung.algorithms.relativelyprime.RelativelyPrime.*;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class RelativelyPrimeUnitTest {
+
+    @Test
+    public void givenNonRelativelyPrimeNumbers_whenCheckingIteratively_shouldReturnFalse() {
+
+        boolean result = iterativeRelativelyPrime(45, 35);
+        assertThat(result).isFalse();
+    }
+
+    @Test
+    public void givenRelativelyPrimeNumbers_whenCheckingIteratively_shouldReturnTrue() {
+
+        boolean result = iterativeRelativelyPrime(500, 501);
+        assertThat(result).isTrue();
+    }
+
+    @Test
+    public void givenNonRelativelyPrimeNumbers_whenCheckingRecursively_shouldReturnFalse() {
+
+        boolean result = recursiveRelativelyPrime(45, 35);
+        assertThat(result).isFalse();
+    }
+
+    @Test
+    public void givenRelativelyPrimeNumbers_whenCheckingRecursively_shouldReturnTrue() {
+
+        boolean result = recursiveRelativelyPrime(500, 501);
+        assertThat(result).isTrue();
+    }
+
+    @Test
+    public void givenNonRelativelyPrimeNumbers_whenCheckingUsingBigIntegers_shouldReturnFalse() {
+
+        boolean result = bigIntegerRelativelyPrime(45, 35);
+        assertThat(result).isFalse();
+    }
+
+    @Test
+    public void givenRelativelyPrimeNumbers_whenCheckingBigIntegers_shouldReturnTrue() {
+
+        boolean result = bigIntegerRelativelyPrime(500, 501);
+        assertThat(result).isTrue();
+    }
+}
@@ -0,0 +1,33 @@
+package com.baeldung.algorithms.reversingtree;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class TreeReverserUnitTest {
+
+    @Test
+    public void givenTreeWhenReversingRecursivelyThenReversed() {
+        TreeReverser reverser = new TreeReverser();
+
+        TreeNode treeNode = reverser.createBinaryTree();
+
+        reverser.reverseRecursive(treeNode);
+
+        assertEquals("4 7 9 6 2 3 1", reverser.toString(treeNode)
+            .trim());
+    }
+
+    @Test
+    public void givenTreeWhenReversingIterativelyThenReversed() {
+        TreeReverser reverser = new TreeReverser();
+
+        TreeNode treeNode = reverser.createBinaryTree();
+
+        reverser.reverseIterative(treeNode);
+
+        assertEquals("4 7 9 6 2 3 1", reverser.toString(treeNode)
+            .trim());
+    }
+
+}
@@ -3,7 +3,3 @@
 ## Core Java Cookbooks and Examples

 ### Relevant Articles: 
- [Immutable ArrayList in Java](http://www.baeldung.com/java-immutable-list)
- [Java - Reading a Large File Efficiently](http://www.baeldung.com/java-read-lines-large-file)
- [Java InputStream to String](http://www.baeldung.com/convert-input-stream-to-string)
-
@@ -0,0 +1,68 @@
+issuer:
+  uri: http://localhost:8080/uaa
+
+spring_profiles: default,hsqldb
+  
+encryption:
+  active_key_label: CHANGE-THIS-KEY
+  encryption_keys:
+    - label: CHANGE-THIS-KEY
+      passphrase: CHANGEME
+
+login:
+  serviceProviderKey: |
+    -----BEGIN RSA PRIVATE KEY-----
+    MIICXQIBAAKBgQDHtC5gUXxBKpEqZTLkNvFwNGnNIkggNOwOQVNbpO0WVHIivig5
+    L39WqS9u0hnA+O7MCA/KlrAR4bXaeVVhwfUPYBKIpaaTWFQR5cTR1UFZJL/OF9vA
+    fpOwznoD66DDCnQVpbCjtDYWX+x6imxn8HCYxhMol6ZnTbSsFW6VZjFMjQIDAQAB
+    AoGAVOj2Yvuigi6wJD99AO2fgF64sYCm/BKkX3dFEw0vxTPIh58kiRP554Xt5ges
+    7ZCqL9QpqrChUikO4kJ+nB8Uq2AvaZHbpCEUmbip06IlgdA440o0r0CPo1mgNxGu
+    lhiWRN43Lruzfh9qKPhleg2dvyFGQxy5Gk6KW/t8IS4x4r0CQQD/dceBA+Ndj3Xp
+    ubHfxqNz4GTOxndc/AXAowPGpge2zpgIc7f50t8OHhG6XhsfJ0wyQEEvodDhZPYX
+    kKBnXNHzAkEAyCA76vAwuxqAd3MObhiebniAU3SnPf2u4fdL1EOm92dyFs1JxyyL
+    gu/DsjPjx6tRtn4YAalxCzmAMXFSb1qHfwJBAM3qx3z0gGKbUEWtPHcP7BNsrnWK
+    vw6By7VC8bk/ffpaP2yYspS66Le9fzbFwoDzMVVUO/dELVZyBnhqSRHoXQcCQQCe
+    A2WL8S5o7Vn19rC0GVgu3ZJlUrwiZEVLQdlrticFPXaFrn3Md82ICww3jmURaKHS
+    N+l4lnMda79eSp3OMmq9AkA0p79BvYsLshUJJnvbk76pCjR28PK4dV1gSDUEqQMB
+    qy45ptdwJLqLJCeNoR0JUcDNIRhOCuOPND7pcMtX6hI/
+    -----END RSA PRIVATE KEY-----
+  serviceProviderKeyPassword: password
+  serviceProviderCertificate: |
+    -----BEGIN CERTIFICATE-----
+    MIIDSTCCArKgAwIBAgIBADANBgkqhkiG9w0BAQQFADB8MQswCQYDVQQGEwJhdzEO
+    MAwGA1UECBMFYXJ1YmExDjAMBgNVBAoTBWFydWJhMQ4wDAYDVQQHEwVhcnViYTEO
+    MAwGA1UECxMFYXJ1YmExDjAMBgNVBAMTBWFydWJhMR0wGwYJKoZIhvcNAQkBFg5h
+    cnViYUBhcnViYS5hcjAeFw0xNTExMjAyMjI2MjdaFw0xNjExMTkyMjI2MjdaMHwx
+    CzAJBgNVBAYTAmF3MQ4wDAYDVQQIEwVhcnViYTEOMAwGA1UEChMFYXJ1YmExDjAM
+    BgNVBAcTBWFydWJhMQ4wDAYDVQQLEwVhcnViYTEOMAwGA1UEAxMFYXJ1YmExHTAb
+    BgkqhkiG9w0BCQEWDmFydWJhQGFydWJhLmFyMIGfMA0GCSqGSIb3DQEBAQUAA4GN
+    ADCBiQKBgQDHtC5gUXxBKpEqZTLkNvFwNGnNIkggNOwOQVNbpO0WVHIivig5L39W
+    qS9u0hnA+O7MCA/KlrAR4bXaeVVhwfUPYBKIpaaTWFQR5cTR1UFZJL/OF9vAfpOw
+    znoD66DDCnQVpbCjtDYWX+x6imxn8HCYxhMol6ZnTbSsFW6VZjFMjQIDAQABo4Ha
+    MIHXMB0GA1UdDgQWBBTx0lDzjH/iOBnOSQaSEWQLx1syGDCBpwYDVR0jBIGfMIGc
+    gBTx0lDzjH/iOBnOSQaSEWQLx1syGKGBgKR+MHwxCzAJBgNVBAYTAmF3MQ4wDAYD
+    VQQIEwVhcnViYTEOMAwGA1UEChMFYXJ1YmExDjAMBgNVBAcTBWFydWJhMQ4wDAYD
+    VQQLEwVhcnViYTEOMAwGA1UEAxMFYXJ1YmExHTAbBgkqhkiG9w0BCQEWDmFydWJh
+    QGFydWJhLmFyggEAMAwGA1UdEwQFMAMBAf8wDQYJKoZIhvcNAQEEBQADgYEAYvBJ
+    0HOZbbHClXmGUjGs+GS+xC1FO/am2suCSYqNB9dyMXfOWiJ1+TLJk+o/YZt8vuxC
+    KdcZYgl4l/L6PxJ982SRhc83ZW2dkAZI4M0/Ud3oePe84k8jm3A7EvH5wi5hvCkK
+    RpuRBwn3Ei+jCRouxTbzKPsuCVB+1sNyxMTXzf0=
+    -----END CERTIFICATE-----
+
+#The secret that an external login server will use to authenticate to the uaa using the id `login`
+LOGIN_SECRET: loginsecret
+
+jwt:
+  token:
+    signing-key: |
+      -----BEGIN RSA PRIVATE KEY-----
+      MIIEpAIBAAKCAQEAqUeygEfDGxI6c1VDQ6xIyUSLrP6iz1y97iHFbtXSxXaArL4a
+      ...
+      v6Mtt5LcRAAVP7pemunTdju4h8Q/noKYlVDVL30uLYUfKBL4UKfOBw==
+      -----END RSA PRIVATE KEY-----
+    verification-key: |
+      -----BEGIN PUBLIC KEY-----
+      MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAqUeygEfDGxI6c1VDQ6xI
+      ...
+      AwIDAQAB
+      -----END PUBLIC KEY-----
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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>
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>2.1.3.RELEASE</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+    <groupId>com.example</groupId>
+    <artifactId>cf-uaa-oauth2-client</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>uaa-client-webapp</name>
+    <description>Demo project for Spring Boot</description>
+
+    <properties>
+        <java.version>1.8</java.version>
+    </properties>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-oauth2-client</artifactId>
+        </dependency>
+
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
@@ -0,0 +1,13 @@
+package com.baeldung.cfuaa.oauth2.client;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class CFUAAOAuth2ClientApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(CFUAAOAuth2ClientApplication.class, args);
+	}
+
+}
@@ -0,0 +1,80 @@
+package com.baeldung.cfuaa.oauth2.client;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.oauth2.client.OAuth2AuthorizedClient;
+import org.springframework.security.oauth2.client.OAuth2AuthorizedClientService;
+import org.springframework.security.oauth2.client.authentication.OAuth2AuthenticationToken;
+import org.springframework.security.oauth2.core.OAuth2AccessToken;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestTemplate;
+
+@RestController
+public class CFUAAOAuth2ClientController {
+
+    @Value("${resource.server.url}")
+    private String remoteResourceServer;
+
+    private RestTemplate restTemplate;
+
+    private OAuth2AuthorizedClientService authorizedClientService;
+
+    public CFUAAOAuth2ClientController(OAuth2AuthorizedClientService authorizedClientService) {
+        this.authorizedClientService = authorizedClientService;
+        this.restTemplate = new RestTemplate();
+    }
+
+    @RequestMapping("/")
+    public String index(OAuth2AuthenticationToken authenticationToken) {
+        OAuth2AuthorizedClient oAuth2AuthorizedClient = this.authorizedClientService.loadAuthorizedClient(authenticationToken.getAuthorizedClientRegistrationId(), authenticationToken.getName());
+        OAuth2AccessToken oAuth2AccessToken = oAuth2AuthorizedClient.getAccessToken();
+
+        String response = "Hello, " + authenticationToken.getPrincipal().getName();
+        response += "</br></br>";
+        response += "Here is your accees token :</br>" + oAuth2AccessToken.getTokenValue();
+        response += "</br>";
+        response += "</br>You can use it to call these Resource Server APIs:";
+        response += "</br></br>";
+        response += "<a href='/read'>Call Resource Server Read API</a>";
+        response += "</br>";
+        response += "<a href='/write'>Call Resource Server Write API</a>";
+        return response;
+    }
+
+    @RequestMapping("/read")
+    public String read(OAuth2AuthenticationToken authenticationToken) {
+        String url = remoteResourceServer + "/read";
+        return callResourceServer(authenticationToken, url);
+    }
+
+    @RequestMapping("/write")
+    public String write(OAuth2AuthenticationToken authenticationToken) {
+        String url = remoteResourceServer + "/write";
+        return callResourceServer(authenticationToken, url);
+    }
+
+    private String callResourceServer(OAuth2AuthenticationToken authenticationToken, String url) {
+        OAuth2AuthorizedClient oAuth2AuthorizedClient = this.authorizedClientService.loadAuthorizedClient(authenticationToken.getAuthorizedClientRegistrationId(), authenticationToken.getName());
+        OAuth2AccessToken oAuth2AccessToken = oAuth2AuthorizedClient.getAccessToken();
+
+        HttpHeaders headers = new HttpHeaders();
+        headers.add("Authorization", "Bearer " + oAuth2AccessToken.getTokenValue());
+
+        HttpEntity<String> entity = new HttpEntity<>("parameters", headers);
+        ResponseEntity<String> responseEntity = null;
+
+        String response = null;
+        try {
+            responseEntity = restTemplate.exchange(url, HttpMethod.GET, entity, String.class);
+            response = responseEntity.getBody();
+        } catch (HttpClientErrorException e) {
+            response = e.getMessage();
+        }
+        return response;
+    }
+}
@@ -0,0 +1,11 @@
+server.port=8081
+
+resource.server.url=http://localhost:8082
+
+spring.security.oauth2.client.registration.uaa.client-name=Web App Client
+spring.security.oauth2.client.registration.uaa.client-id=webappclient
+spring.security.oauth2.client.registration.uaa.client-secret=webappclientsecret
+spring.security.oauth2.client.registration.uaa.scope=resource.read,resource.write,openid,profile
+
+spring.security.oauth2.client.provider.uaa.issuer-uri=http://localhost:8080/uaa/oauth/token
+
@@ -0,0 +1 @@
+tintin
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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>
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>2.1.3.RELEASE</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+    <groupId>com.baeldung.cfuaa</groupId>
+    <artifactId>cf-uaa-oauth2-resource-server</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>cf-uaa-oauth2-resource-server</name>
+    <description>Demo project for Spring Boot</description>
+
+    <properties>
+        <java.version>1.8</java.version>
+    </properties>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-oauth2-resource-server</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
@@ -0,0 +1,13 @@
+package com.baeldung.cfuaa.oauth2.resourceserver;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class CFUAAOAuth2ResourceServerApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(CFUAAOAuth2ResourceServerApplication.class, args);
+	}
+
+}
@@ -0,0 +1,28 @@
+package com.baeldung.cfuaa.oauth2.resourceserver;
+
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.security.oauth2.jwt.Jwt;
+import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationToken;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.security.Principal;
+
+@RestController
+public class CFUAAOAuth2ResourceServerRestController {
+
+    @GetMapping("/")
+    public String index(@AuthenticationPrincipal Jwt jwt) {
+        return String.format("Hello, %s!", jwt.getSubject());
+    }
+
+    @GetMapping("/read")
+    public String read(JwtAuthenticationToken jwtAuthenticationToken) {
+        return "Hello write: " + jwtAuthenticationToken.getTokenAttributes();
+    }
+
+    @GetMapping("/write")
+    public String write(Principal principal) {
+        return "Hello write: " + principal.getName();
+    }
+}
@@ -0,0 +1,21 @@
+package com.baeldung.cfuaa.oauth2.resourceserver;
+
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+
+@EnableWebSecurity
+public class CFUAAOAuth2ResourceServerSecurityConfiguration extends WebSecurityConfigurerAdapter {
+
+	@Override
+	protected void configure(HttpSecurity http) throws Exception {
+		http
+			.authorizeRequests()
+                .antMatchers("/read/**").hasAuthority("SCOPE_resource.read")
+                .antMatchers("/write/**").hasAuthority("SCOPE_resource.write")
+                .anyRequest().authenticated()
+				.and()
+			.oauth2ResourceServer()
+				.jwt();
+	}
+}
@@ -0,0 +1,3 @@
+server.port=8082
+
+spring.security.oauth2.resourceserver.jwt.issuer-uri=http://localhost:8080/uaa/oauth/token
@@ -8,3 +8,6 @@
 - [Types of Strings in Groovy](https://www.baeldung.com/groovy-strings)
 - [A Quick Guide to Iterating a Map in Groovy](https://www.baeldung.com/groovy-map-iterating)
 - [An Introduction to Traits in Groovy](https://www.baeldung.com/groovy-traits)
+- [Lists in Groovy](https://www.baeldung.com/groovy-lists)
+- [Converting a String to a Date in Groovy](https://www.baeldung.com/groovy-string-to-date)
+- [Guide to I/O in Groovy](https://www.baeldung.com/groovy-io)
@@ -0,0 +1,37 @@
+package com.baeldung
+
+class Person {
+    private String firstname
+    private String lastname
+    private Integer age
+
+    Person(String firstname, String lastname, Integer age) {
+        this.firstname = firstname
+        this.lastname = lastname
+        this.age = age
+    }
+
+    String getFirstname() {
+        return firstname
+    }
+
+    void setFirstname(String firstname) {
+        this.firstname = firstname
+    }
+
+    String getLastname() {
+        return lastname
+    }
+
+    void setLastname(String lastname) {
+        this.lastname = lastname
+    }
+
+    Integer getAge() {
+        return age
+    }
+
+    void setAge(Integer age) {
+        this.age = age
+    }
+}
@@ -0,0 +1,87 @@
+package com.baeldung.closures
+
+class Closures {
+    
+    def printWelcome = {
+        println "Welcome to Closures!"
+    }
+    
+    def print = { name ->
+        println name
+    }
+    
+    def formatToLowerCase(name) {
+        return name.toLowerCase()
+    }
+    def formatToLowerCaseClosure = { name ->
+        return name.toLowerCase()
+    }
+    
+    def count=0
+    
+    def increaseCount = {
+        count++
+    }
+    
+    def greet = {
+        return "Hello! ${it}"
+    }
+   
+    def multiply = { x, y ->
+        return x*y
+    }
+    
+    def calculate = {int x, int y, String operation ->
+        
+        //log closure
+        def log = {
+            println "Performing $it"
+        }
+        
+        def result = 0    
+        switch(operation) {
+            case "ADD":
+                log("Addition")
+                result = x+y
+                break
+            case "SUB":
+                log("Subtraction")
+                result = x-y
+                break
+            case "MUL":
+                log("Multiplication")
+                result = x*y
+                break
+            case "DIV":
+                log("Division")
+                result = x/y
+                break
+        }
+        return result
+    }
+    
+    def addAll = { int... args ->
+        return args.sum()
+    }
+    
+    def volume(Closure areaCalculator, int... dimensions) {
+        if(dimensions.size() == 3) {
+            
+            //consider dimension[0] = length, dimension[1] = breadth, dimension[2] = height
+            //for cube and cuboid
+            return areaCalculator(dimensions[0], dimensions[1]) * dimensions[2]
+        } else if(dimensions.size() == 2) {
+            
+            //consider dimension[0] = radius, dimension[1] = height
+            //for cylinder and cone
+            return areaCalculator(dimensions[0]) * dimensions[1]
+        } else if(dimensions.size() == 1) {
+            
+            //consider dimension[0] = radius
+            //for sphere
+            return areaCalculator(dimensions[0]) * dimensions[0]
+        }
+        
+    }
+     
+}
@@ -0,0 +1,6 @@
+package com.baeldung.closures
+
+class Employee {
+    
+    String fullName
+}
@@ -0,0 +1,80 @@
+package com.baeldung.closures
+
+import spock.lang.Specification
+
+class ClosuresUnitTest extends GroovyTestCase {
+
+    Closures closures = new Closures()
+    
+    void testDeclaration() {
+        
+        closures.print("Hello! Closure")
+        closures.formatToLowerCaseClosure("Hello! Closure")
+        
+        closures.print.call("Hello! Closure")
+        closures.formatToLowerCaseClosure.call("Hello! Closure")
+        
+    }
+    
+    void testClosureVsMethods() {   
+        assert closures.formatToLowerCase("TONY STARK") == closures.formatToLowerCaseClosure("Tony STark")
+    }
+    
+    void testParameters() {
+        //implicit parameter
+        assert closures.greet("Alex") == "Hello! Alex"
+        
+        //multiple parameters
+        assert closures.multiply(2, 4) == 8
+        
+        assert closures.calculate(12, 4, "ADD") == 16
+        assert closures.calculate(12, 4, "SUB") == 8
+        assert closures.calculate(43, 8, "DIV") == 5.375
+                
+        //varags
+        assert closures.addAll(12, 10, 14) == 36
+       
+    }
+    
+    void testClosureAsAnArgument() {
+        assert closures.volume({ l, b -> return l*b }, 12, 6, 10) == 720
+        
+        assert closures.volume({ radius -> return Math.PI*radius*radius/3 }, 5, 10) == Math.PI * 250/3
+    }
+    
+    void testGStringsLazyEvaluation() {
+        def name = "Samwell"
+        def welcomeMsg = "Welcome! $name"
+        
+        assert welcomeMsg == "Welcome! Samwell"
+        
+        // changing the name does not affect original interpolated value
+        name = "Tarly"
+        assert welcomeMsg != "Welcome! Tarly"
+        
+        def fullName = "Tarly Samson"
+        def greetStr = "Hello! ${-> fullName}"
+        
+        assert greetStr == "Hello! Tarly Samson"
+
+        // this time changing the variable affects the interpolated String's value
+        fullName = "Jon Smith"
+        assert greetStr == "Hello! Jon Smith"
+    }
+    
+    void testClosureInLists() {
+        def list = [10, 11, 12, 13, 14, true, false, "BUNTHER"]
+        list.each {
+            println it
+        }
+        
+        assert [13, 14] == list.findAll{ it instanceof Integer && it >= 13}
+    }
+    
+    void testClosureInMaps() {
+        def map = [1:10, 2:30, 4:5]
+        
+        assert [10, 60, 20] == map.collect{it.key * it.value}
+    }
+    
+}
@@ -129,13 +129,13 @@ class ListTest{
        assertTrue(filterList.findAll{it > 3} == [4, 5, 6, 76])

        assertTrue(filterList.findAll{ it instanceof Number} == [2, 1, 3, 4, 5, 6, 76])
-        
+
        assertTrue(filterList.grep( Number )== [2, 1, 3, 4, 5, 6, 76])
-        
+
        assertTrue(filterList.grep{ it> 6 }== [76])

        def conditionList = [2, 1, 3, 4, 5, 6, 76]
-        
+
        assertFalse(conditionList.every{ it < 6})

        assertTrue(conditionList.any{ it%2 == 0})
@@ -165,7 +165,7 @@ class ListTest{

        def strList = ["na", "ppp", "as"]
        assertTrue(strList.max() == "ppp")
-        
+
        Comparator minc = {a,b -> a == b? 0: a < b? -1 : 1}
        def numberList = [3, 2, 0, 7]
        assertTrue(numberList.min(minc) == 0)
@@ -0,0 +1,58 @@
+package com.baeldung.lists
+
+import com.baeldung.Person
+import org.junit.Test
+
+import static org.junit.Assert.*
+
+class ListUnitTest {
+
+    private final personList = [
+      new Person("Regina", "Fitzpatrick", 25),
+      new Person("Abagail", "Ballard", 26),
+      new Person("Lucian", "Walter", 30),
+    ]
+
+    @Test
+    void whenListContainsElement_thenCheckReturnsTrue() {
+        def list = ['a', 'b', 'c']
+
+        assertTrue(list.indexOf('a') > -1)
+        assertTrue(list.contains('a'))
+    }
+
+    @Test
+    void whenListContainsElement_thenCheckWithMembershipOperatorReturnsTrue() {
+        def list = ['a', 'b', 'c']
+
+        assertTrue('a' in list)
+    }
+
+    @Test
+    void givenListOfPerson_whenUsingStreamMatching_thenShouldEvaluateList() {
+        assertTrue(personList.stream().anyMatch {it.age > 20})
+        assertFalse(personList.stream().allMatch {it.age < 30})
+    }
+
+    @Test
+    void givenListOfPerson_whenUsingCollectionMatching_thenShouldEvaluateList() {
+        assertTrue(personList.any {it.age > 20})
+        assertFalse(personList.every {it.age < 30})
+    }
+
+    @Test
+    void givenListOfPerson_whenUsingStreamFind_thenShouldReturnMatchingElements() {
+        assertTrue(personList.stream().filter {it.age > 20}.findAny().isPresent())
+        assertFalse(personList.stream().filter {it.age > 30}.findAny().isPresent())
+        assertTrue(personList.stream().filter {it.age > 20}.findAll().size() == 3)
+        assertTrue(personList.stream().filter {it.age > 30}.findAll().isEmpty())
+    }
+
+    @Test
+    void givenListOfPerson_whenUsingCollectionFind_thenShouldReturnMatchingElements() {
+        assertNotNull(personList.find {it.age > 20})
+        assertNull(personList.find {it.age > 30})
+        assertTrue(personList.findAll {it.age > 20}.size() == 3)
+        assertTrue(personList.findAll {it.age > 30}.isEmpty())
+    }
+}
@@ -1,10 +1,18 @@
 package com.baeldung.map

-import static org.junit.Assert.*
+import com.baeldung.Person
 import org.junit.Test

+import static org.junit.Assert.*
+
 class MapUnitTest {

+    private final personMap = [
+      Regina : new Person("Regina", "Fitzpatrick", 25),
+      Abagail: new Person("Abagail", "Ballard", 26),
+      Lucian : new Person("Lucian", "Walter", 30)
+    ]
+
    @Test
    void whenUsingEach_thenMapIsIterated() {
        def map = [
@@ -63,7 +71,7 @@ class MapUnitTest {
            'FF6347' : 'Tomato',
            'FF4500' : 'Orange Red'
        ]
-        
+
        map.eachWithIndex { key, val, index ->
            def indent = ((index == 0 || index % 2 == 0) ? "   " : "")
            println "$indent Hex Code: $key = Color Name: $val"
@@ -82,4 +90,65 @@ class MapUnitTest {
            println "Hex Code: $entry.key = Color Name: $entry.value"
        }
    }
+
+    @Test
+    void whenMapContainsKeyElement_thenCheckReturnsTrue() {
+        def map = [a: 'd', b: 'e', c: 'f']
+
+        assertTrue(map.containsKey('a'))
+        assertFalse(map.containsKey('e'))
+        assertTrue(map.containsValue('e'))
+    }
+
+    @Test
+    void whenMapContainsKeyElement_thenCheckByMembershipReturnsTrue() {
+        def map = [a: 'd', b: 'e', c: 'f']
+
+        assertTrue('a' in map)
+        assertFalse('f' in map)
+    }
+
+    @Test
+    void whenMapContainsFalseBooleanValues_thenCheckReturnsFalse() {
+        def map = [a: true, b: false, c: null]
+
+        assertTrue(map.containsKey('b'))
+        assertTrue('a' in map)
+        assertFalse('b' in map)
+        assertFalse('c' in map)
+    }
+
+    @Test
+    void givenMapOfPerson_whenUsingStreamMatching_thenShouldEvaluateMap() {
+        assertTrue(personMap.keySet().stream().anyMatch {it == "Regina"})
+        assertFalse(personMap.keySet().stream().allMatch {it == "Albert"})
+        assertFalse(personMap.values().stream().allMatch {it.age < 30})
+        assertTrue(personMap.entrySet().stream().anyMatch {it.key == "Abagail" && it.value.lastname == "Ballard"})
+    }
+
+    @Test
+    void givenMapOfPerson_whenUsingCollectionMatching_thenShouldEvaluateMap() {
+        assertTrue(personMap.keySet().any {it == "Regina"})
+        assertFalse(personMap.keySet().every {it == "Albert"})
+        assertFalse(personMap.values().every {it.age < 30})
+        assertTrue(personMap.any {firstname, person -> firstname == "Abagail" && person.lastname == "Ballard"})
+    }
+
+    @Test
+    void givenMapOfPerson_whenUsingCollectionFind_thenShouldReturnElements() {
+        assertNotNull(personMap.find {it.key == "Abagail" && it.value.lastname == "Ballard"})
+        assertTrue(personMap.findAll {it.value.age > 20}.size() == 3)
+    }
+
+    @Test
+    void givenMapOfPerson_whenUsingStreamFind_thenShouldReturnElements() {
+        assertTrue(
+          personMap.entrySet().stream()
+            .filter {it.key == "Abagail" && it.value.lastname == "Ballard"}
+            .findAny().isPresent())
+        assertTrue(
+          personMap.entrySet().stream()
+            .filter {it.value.age > 20}
+            .findAll().size() == 3)
+    }
 }
@@ -0,0 +1,16 @@
+package com.baeldung.set
+
+import org.junit.Test
+
+import static org.junit.Assert.assertTrue
+
+class SetUnitTest {
+
+    @Test
+    void whenSetContainsElement_thenCheckReturnsTrue() {
+        def set = ['a', 'b', 'c'] as Set
+
+        assertTrue(set.contains('a'))
+        assertTrue('a' in set)
+    }
+}
@@ -4,3 +4,5 @@
 - [Java 11 Local Variable Syntax for Lambda Parameters](https://www.baeldung.com/java-var-lambda-params)
 - [Java 11 String API Additions](https://www.baeldung.com/java-11-string-api)
 - [Java 11 Nest Based Access Control](https://www.baeldung.com/java-nest-based-access-control)
+- [Exploring the New HTTP Client in Java 9 and 11](https://www.baeldung.com/java-9-http-client)
+- [An Introduction to Epsilon GC: A No-Op Experimental Garbage Collector](https://www.baeldung.com/jvm-epsilon-gc-garbage-collector)
@@ -0,0 +1,12 @@
+package com.baeldung.jlink;
+
+import java.util.logging.Logger;
+
+public class HelloWorld {
+
+    private static final Logger LOG = Logger.getLogger(HelloWorld.class.getName());
+
+    public static void main(String[] args) {
+        LOG.info("Hello World!");
+    }
+}
@@ -0,0 +1,3 @@
+module jlinkModule {
+    requires java.logging;
+}
--- a/Show More
+++ b/Show More