Merge remote-tracking branch 'origin/master'

core-java/src/main/java/com/baeldung/exceptions/StackTraceToString.java

@@ -0,0 +1,30 @@
+package com.baeldung.exceptions;
+
+import org.apache.commons.lang3.exception.ExceptionUtils;
+
+import java.io.PrintWriter;
+import java.io.StringWriter;
+
+public class StackTraceToString {
+
+    public static void main(String[] args) {
+        // Convert a StackTrace to String using core java
+        try {
+            throw new NullPointerException();
+        } catch (Exception e) {
+            StringWriter sw = new StringWriter();
+            PrintWriter pw = new PrintWriter(sw);
+            e.printStackTrace(pw);
+
+            System.out.println(sw.toString());
+        }
+
+        // Convert a StackTrace to String using Apache Commons
+        try {
+            throw new IndexOutOfBoundsException();
+        } catch (Exception e) {
+            System.out.println(ExceptionUtils.getStackTrace(e));
+        }
+    }
+
+}

core-java/src/test/java/com/baeldung/java8/comparator/Employee.java

@@ -1,6 +1,4 @@
 package com.baeldung.java8.comparator;
-/*    
-
 import lombok.AllArgsConstructor;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
@@ -22,4 +20,3 @@ public class Employee implements Comparable<Employee>{
     }
     
 }
-*/

core-java/src/test/java/com/baeldung/java8/comparator/Java8ComparatorTest.java

@@ -1,5 +1,4 @@
 package com.baeldung.java8.comparator;
-/*
 import java.util.Arrays;
 import java.util.Comparator;
 
@@ -164,5 +163,3 @@ public class Java8ComparatorTest {
 
 
 }
-
-*/

guava/src/test/java/org/baeldung/guava/ClassToInstanceMapTests.java

@@ -0,0 +1,70 @@
+package org.baeldung.guava;
+import com.google.common.collect.ClassToInstanceMap;
+import com.google.common.collect.ImmutableClassToInstanceMap;
+import com.google.common.collect.MutableClassToInstanceMap;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class ClassToInstanceMapTests {
+    @Test
+    public void createEmptyImmutableMap() {
+        ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of();
+        assertTrue(map.isEmpty());
+    }
+
+    @Test
+    public void createEmptyMutableMap() {
+        ClassToInstanceMap<Action> map = MutableClassToInstanceMap.create();
+        assertTrue(map.isEmpty());
+    }
+
+    @Test
+    public void createSingleEntryMap() {
+        ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of(Save.class, new Save());
+        assertEquals(1, map.size());
+    }
+
+    @Test
+    public void createMapWithBuilder() {
+        ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.<Action>builder()
+                .put(Save.class, new Save())
+                .put(Open.class, new Open())
+                .build();
+        assertEquals(2, map.size());
+    }
+
+    @Test
+    public void shouldReturnElement() {
+        ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of(Save.class, new Save());
+        Action action = map.get(Save.class);
+        assertTrue(action instanceof Save);
+
+        // Use getInstance to avoid casting
+        Save save = map.getInstance(Save.class);
+    }
+
+    @Test
+    public void shouldPutElement() {
+        ClassToInstanceMap<Action> map = MutableClassToInstanceMap.create();
+        map.put(Save.class, new Save());
+        // Put again to get previous value returned
+        Action action = map.put(Save.class, new Save());
+        assertTrue(action instanceof Save);
+
+        // Use putInstance to avoid casting
+        Save save = map.putInstance(Save.class, new Save());
+    }
+}
+
+abstract class Action {
+}
+
+class Save extends Action {
+}
+
+class Open extends Action {
+}
+
+class Delete extends Action {
+}

guava21/src/test/java/GuavaStreamsTests.java

@@ -9,7 +9,7 @@ import java.util.stream.IntStream;
 import java.util.stream.LongStream;
 import java.util.stream.Stream;
 
-public class GauavaStreamsTests {
+public class GuavaStreamsTests {
 
     List<Integer> numbers;
 

libraries/myPersistence.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?><root>
+    
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+
+    
+    
+</root>

libraries/pom.xml

@@ -251,6 +251,11 @@
 		    <artifactId>h2</artifactId>
 		    <version>1.4.194</version>
 		</dependency>
+		<dependency>
+		    <groupId>org.datanucleus</groupId>
+		    <artifactId>datanucleus-xml</artifactId>
+		    <version>5.0.0-release</version>
+		</dependency>		
     </dependencies>
 
     <properties>

libraries/src/main/java/com/baeldung/jdo/GuideToJDO.java

@@ -20,22 +20,29 @@ public class GuideToJDO {
     private static final Logger LOGGER = Logger.getLogger(GuideToJDO.class.getName());
     private Random rnd = new Random();
     private PersistenceUnitMetaData pumd;
+    private PersistenceUnitMetaData pumdXML;
 
     public static void main(String[] args) {
         new GuideToJDO();
     }
 
     public GuideToJDO() {
-        CreateProperties();
+        CreateH2Properties();
+        CreateXMLProperties();
         CreateProducts();
         ListProducts();
+        QueryJDOQL();
+        QuerySQL();
+        QueryJPQL();
         UpdateProducts();
         ListProducts();
         DeleteProducts();
         ListProducts();
+        persistXML();
+        listXMLProducts();
     }
 
-    public void CreateProperties(){
+    public void CreateH2Properties(){
         
         pumd = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
         pumd.addClassName("com.baeldung.jdo.Product");
@@ -48,6 +55,14 @@ public class GuideToJDO {
         
     }
     
+    public void CreateXMLProperties(){
+        pumdXML = new PersistenceUnitMetaData("dynamic-unit", "RESOURCE_LOCAL", null);
+        pumdXML.addClassName("com.baeldung.jdo.ProductXML");
+        pumdXML.setExcludeUnlistedClasses();
+        pumdXML.addProperty("javax.jdo.option.ConnectionURL", "xml:file:myPersistence.xml");
+        pumdXML.addProperty("datanucleus.autoCreateSchema", "true");        
+    }
+    
     public void CreateProducts() {
         PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumd, null);
         PersistenceManager pm = pmf.getPersistenceManager();
@@ -140,4 +155,145 @@ public class GuideToJDO {
             pm.close();
         }
     }
+    
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    public void QueryJDOQL (){
+        PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumd, null);
+        PersistenceManager pm = pmf.getPersistenceManager();
+        Transaction tx = pm.currentTransaction();
+        try {
+            tx.begin();
+
+            // Declarative JDOQL :
+            LOGGER.log(Level.INFO, "Declarative JDOQL --------------------------------------------------------------");
+            Query qDJDOQL = pm.newQuery(Product.class);
+            qDJDOQL.setFilter("name == 'Tablet' && price == price_value");
+            qDJDOQL.declareParameters("double price_value");
+            List<Product> resultsqDJDOQL = qDJDOQL.setParameters(80.0).executeList();
+
+            Iterator<Product> iterDJDOQL = resultsqDJDOQL.iterator();
+            while (iterDJDOQL.hasNext()) {
+                Product p = iterDJDOQL.next();
+                LOGGER.log(Level.WARNING, "Product name: {0} - Price: {1}", new Object[] { p.name, p.price });
+            }
+            LOGGER.log(Level.INFO, "--------------------------------------------------------------");
+            
+            tx.commit();
+        } finally {
+            if (tx.isActive()) {
+                tx.rollback();
+            }
+
+            pm.close();
+        }
+    }
+    
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    public void QuerySQL (){
+        PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumd, null);
+        PersistenceManager pm = pmf.getPersistenceManager();
+        Transaction tx = pm.currentTransaction();
+        try {
+            tx.begin();
+
+            //SQL :
+            LOGGER.log(Level.INFO, "SQL --------------------------------------------------------------");
+            Query query = pm.newQuery("javax.jdo.query.SQL", "SELECT * FROM PRODUCT");
+            query.setClass(Product.class);
+            List<Product> results = query.executeList();
+            
+            Iterator<Product> iter = results.iterator();
+            while (iter.hasNext()) {
+                Product p = iter.next();
+                LOGGER.log(Level.WARNING, "Product name: {0} - Price: {1}", new Object[] { p.name, p.price });
+            }
+            LOGGER.log(Level.INFO, "--------------------------------------------------------------");
+            
+            tx.commit();
+        } finally {
+            if (tx.isActive()) {
+                tx.rollback();
+            }
+
+            pm.close();
+        }
+    }
+    
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    public void QueryJPQL (){
+        PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumd, null);
+        PersistenceManager pm = pmf.getPersistenceManager();
+        Transaction tx = pm.currentTransaction();
+        try {
+            tx.begin();
+
+            //JPQL :
+            LOGGER.log(Level.INFO, "JPQL --------------------------------------------------------------");
+            Query q = pm.newQuery("JPQL", "SELECT p FROM "+Product.class.getName()+" p WHERE p.name = 'Laptop'");
+            List results = (List)q.execute();
+            
+            Iterator<Product> iter = results.iterator();
+            while (iter.hasNext()) {
+                Product p = iter.next();
+                LOGGER.log(Level.WARNING, "Product name: {0} - Price: {1}", new Object[] { p.name, p.price });
+            }
+            LOGGER.log(Level.INFO, "--------------------------------------------------------------");
+            
+            tx.commit();
+        } finally {
+            if (tx.isActive()) {
+                tx.rollback();
+            }
+
+            pm.close();
+        }
+    }
+    
+    public void persistXML(){
+        PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumdXML, null);
+        PersistenceManager pm = pmf.getPersistenceManager();
+        Transaction tx = pm.currentTransaction();
+        try {
+            tx.begin();
+            ProductXML productXML = new ProductXML(0,"Tablet", 80.0);
+            pm.makePersistent(productXML);
+            ProductXML productXML2 = new ProductXML(1,"Phone", 20.0);
+            pm.makePersistent(productXML2);
+            ProductXML productXML3 = new ProductXML(2,"Laptop", 200.0);
+            pm.makePersistent(productXML3);
+            tx.commit();
+        } finally {
+            if (tx.isActive()) {
+                tx.rollback();
+            }
+            pm.close();
+        }
+    }
+    
+    @SuppressWarnings({ "rawtypes", "unchecked" })
+    public void listXMLProducts(){
+        PersistenceManagerFactory pmf = new JDOPersistenceManagerFactory(pumdXML, null);
+        PersistenceManager pm = pmf.getPersistenceManager();
+        Transaction tx = pm.currentTransaction();
+        try {
+            tx.begin();
+
+            Query q = pm.newQuery("SELECT FROM " + ProductXML.class.getName());
+            List<ProductXML> products = (List<ProductXML>) q.execute();
+            Iterator<ProductXML> iter = products.iterator();
+            while (iter.hasNext()) {
+                ProductXML p = iter.next();
+                LOGGER.log(Level.WARNING, "Product name: {0} - Price: {1}", new Object[] { p.getName(), p.getPrice() });
+                pm.deletePersistent(p);
+            }
+            LOGGER.log(Level.INFO, "--------------------------------------------------------------");
+            tx.commit();
+        } finally {
+            if (tx.isActive()) {
+                tx.rollback();
+            }
+
+            pm.close();
+        }
+    }
 }

libraries/src/main/java/com/baeldung/jdo/ProductXML.java

@@ -0,0 +1,44 @@
+package com.baeldung.jdo;
+
+import javax.jdo.annotations.PersistenceCapable;
+import javax.jdo.annotations.PrimaryKey;
+import javax.xml.bind.annotation.XmlAttribute;
+
+@PersistenceCapable()
+public class ProductXML {
+
+    @XmlAttribute
+    private long productNumber = 0;
+    @PrimaryKey
+    private String name = null;
+    private Double price = 0.0;
+
+    public ProductXML() {
+        this.productNumber = 0;
+        this.name = null;
+        this.price = 0.0;
+    }
+
+    public ProductXML(long productNumber, String name, Double price) {
+        this.productNumber = productNumber;
+        this.name = name;
+        this.price = price;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Double getPrice() {
+        return price;
+    }
+
+    public void setPrice(Double price) {
+        this.price = price;
+    }
+
+}

pom.xml

@@ -212,6 +212,7 @@
         <module>spring-data-gemfire</module>
         <module>cucumber</module>
         <module>mybatis</module>
+        <module>spring-drools</module>
     </modules>
 
     <build>

spring-drools/pom.xml

@@ -0,0 +1,130 @@
+<?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>
+
+    <groupId>com.baeldung</groupId>
+    <artifactId>spring-drools</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <properties>
+        <spring-boot-version>1.1.1.RELEASE</spring-boot-version>
+        <http-component-version>4.0-alpha6</http-component-version>
+        <drools-version>7.0.0.CR1</drools-version>
+        <apache-poi-version>3.13</apache-poi-version>
+        <surefire-plugin-version>2.19.1</surefire-plugin-version>
+    </properties>
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>io.spring.platform</groupId>
+                <artifactId>platform-bom</artifactId>
+                <version>${spring-boot-version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-actuator</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.httpcomponents</groupId>
+            <artifactId>httpcore</artifactId>
+            <version>${http-component-version}</version>
+        </dependency>
+        <!-- ... -->
+        <dependency>
+            <groupId>org.kie</groupId>
+            <artifactId>kie-ci</artifactId>
+            <version>${drools-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.drools</groupId>
+            <artifactId>drools-decisiontables</artifactId>
+            <version>${drools-version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.drools</groupId>
+            <artifactId>drools-core</artifactId>
+            <version>${drools-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.drools</groupId>
+            <artifactId>drools-compiler</artifactId>
+            <version>${drools-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi</artifactId>
+            <version>${apache-poi-version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi-ooxml</artifactId>
+            <version>${apache-poi-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.kie</groupId>
+            <artifactId>kie-spring</artifactId>
+            <version>6.4.0.Final</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-tx</artifactId>
+                </exclusion>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-beans</artifactId>
+                </exclusion>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-core</artifactId>
+                </exclusion>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-context</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>repackage</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>${surefire-plugin-version}</version>
+                <configuration>
+                    <excludes>
+                        <exclude>**/*IntegrationTest.java</exclude>
+                    </excludes>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

spring-drools/src/main/java/com/baeldung/spring/drools/Application.java

@@ -0,0 +1,30 @@
+package com.baeldung.spring.drools;
+
+
+import com.baeldung.spring.drools.model.Applicant;
+import com.baeldung.spring.drools.model.Product;
+import com.baeldung.spring.drools.model.SuggestedRole;
+import com.baeldung.spring.drools.service.ApplicantService;
+import com.baeldung.spring.drools.service.ProductService;
+import org.kie.api.KieServices;
+import org.kie.api.runtime.KieContainer;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Import;
+
+@SpringBootApplication
+@Import(DroolConfiguration.class)
+public class Application {
+
+    public static void main(String[] args) {
+        ApplicationContext ctx = SpringApplication.run(Application.class, args);
+        ApplicantService applicantService=(ApplicantService)ctx.getBean("applicantService");
+        applicantService.suggestARoleForApplicant(new Applicant("Baljeet",37,1200000.0,8),new SuggestedRole());
+
+        ProductService productService=(ProductService)ctx.getBean("productService");
+        Product returnedProduct=productService.applyLabelToProduct(new Product("Microwave","Book"));
+    }
+
+}

spring-drools/src/main/java/com/baeldung/spring/drools/DroolConfiguration.java

@@ -0,0 +1,83 @@
+package com.baeldung.spring.drools;
+
+import com.baeldung.spring.drools.service.ApplicantService;
+import com.baeldung.spring.drools.service.ProductService;
+import org.kie.api.KieBase;
+import org.kie.api.KieServices;
+import org.kie.api.builder.*;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.kie.internal.io.ResourceFactory;
+import org.kie.spring.KModuleBeanFactoryPostProcessor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
+import org.springframework.core.io.support.ResourcePatternResolver;
+
+import java.io.IOException;
+
+@Configuration
+public class DroolConfiguration {
+
+    private static final String RULES_PATH = "com/baeldung/spring/drools/rules/";
+
+    @Bean
+    public KieFileSystem kieFileSystem() throws IOException {
+        KieFileSystem kieFileSystem = getKieServices().newKieFileSystem();
+        for (Resource file : getRuleFiles()) {
+            kieFileSystem.write(ResourceFactory.newClassPathResource(RULES_PATH + file.getFilename(), "UTF-8"));
+        }
+        return kieFileSystem;
+    }
+
+    private Resource[] getRuleFiles() throws IOException {
+        ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
+        return resourcePatternResolver.getResources("classpath*:" + RULES_PATH + "**/*.*");
+    }
+
+    @Bean
+    public KieContainer kieContainer() throws IOException {
+        final KieRepository kieRepository = getKieServices().getRepository();
+
+        kieRepository.addKieModule(new KieModule() {
+            public ReleaseId getReleaseId() {
+                return kieRepository.getDefaultReleaseId();
+            }
+        });
+
+        KieBuilder kieBuilder = getKieServices().newKieBuilder(kieFileSystem());
+        kieBuilder.buildAll();
+
+        return getKieServices().newKieContainer(kieRepository.getDefaultReleaseId());
+    }
+
+    private KieServices getKieServices() {
+        return KieServices.Factory.get();
+    }
+
+    @Bean
+    public KieBase kieBase() throws IOException {
+        return kieContainer().getKieBase();
+    }
+
+    @Bean
+    public KieSession kieSession() throws IOException {
+        return kieContainer().newKieSession();
+    }
+
+    @Bean
+    public ApplicantService getApplicantService(){
+        return new ApplicantService();
+    }
+
+    @Bean
+    public ProductService getProductService(KieContainer kieContainer){
+        return new ProductService();
+    }
+
+    @Bean
+    public KModuleBeanFactoryPostProcessor kiePostProcessor() {
+        return new KModuleBeanFactoryPostProcessor();
+    }
+}

spring-drools/src/main/java/com/baeldung/spring/drools/model/Applicant.java

@@ -0,0 +1,48 @@
+package com.baeldung.spring.drools.model;
+
+public class Applicant {
+
+    private String name;
+    private int age;
+    private double currentSalary;
+    private int experienceInYears;
+
+    public Applicant(String name, int age, Double currentSalary, int experienceInYears) {
+        this.name = name;
+        this.age = age;
+        this.currentSalary = currentSalary;
+        this.experienceInYears = experienceInYears;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    public Double getCurrentSalary() {
+        return currentSalary;
+    }
+
+    public void setCurrentSalary(Double currentSalary) {
+        this.currentSalary = currentSalary;
+    }
+
+    public int getExperienceInYears() {
+        return experienceInYears;
+    }
+
+    public void setExperienceInYears(int experienceInYears) {
+        this.experienceInYears = experienceInYears;
+    }
+}

spring-drools/src/main/java/com/baeldung/spring/drools/model/Product.java

@@ -0,0 +1,38 @@
+package com.baeldung.spring.drools.model;
+
+public class Product {
+    private String name;
+    private String type;
+
+    private String label;
+
+    public Product(String name, String type) {
+        this.name = name;
+        this.type = type;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public String getLabel() {
+        return label;
+    }
+
+    public void setLabel(String label) {
+        this.label = label;
+    }
+
+}

spring-drools/src/main/java/com/baeldung/spring/drools/model/SuggestedRole.java

@@ -0,0 +1,14 @@
+package com.baeldung.spring.drools.model;
+
+public class SuggestedRole {
+
+    private String role;
+
+    public String getRole() {
+        return role;
+    }
+
+    public void setRole(String role) {
+        this.role = role;
+    }
+}

spring-drools/src/main/java/com/baeldung/spring/drools/service/ApplicantService.java

@@ -0,0 +1,25 @@
+package com.baeldung.spring.drools.service;
+
+import com.baeldung.spring.drools.model.Applicant;
+import com.baeldung.spring.drools.model.SuggestedRole;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+@Service
+public class ApplicantService {
+
+    @Autowired
+    private KieContainer kieContainer;
+
+    public SuggestedRole suggestARoleForApplicant(Applicant applicant,SuggestedRole suggestedRole){
+        KieSession kieSession = kieContainer.newKieSession();
+        kieSession.insert(applicant);
+        kieSession.setGlobal("suggestedRole",suggestedRole);
+        kieSession.fireAllRules();
+        System.out.println(suggestedRole.getRole());
+        return  suggestedRole;
+
+    }
+}

spring-drools/src/main/java/com/baeldung/spring/drools/service/ProductService.java

@@ -0,0 +1,24 @@
+package com.baeldung.spring.drools.service;
+
+import com.baeldung.spring.drools.model.Product;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+@Service
+public class ProductService {
+
+    @Autowired
+    private  KieContainer kieContainer;
+
+    public Product applyLabelToProduct(Product product){
+        KieSession kieSession = kieContainer.newKieSession();
+        kieSession.insert(product);
+        kieSession.fireAllRules();
+        System.out.println(product.getLabel());
+        return  product;
+
+    }
+
+}

spring-drools/src/main/resources/com/baeldung/spring/drools/rules/SuggestApplicant.drl

@@ -0,0 +1,31 @@
+package com.baeldung.spring.drools.rules;
+
+import com.baeldung.spring.drools.model.Applicant;
+
+global com.baeldung.spring.drools.model.SuggestedRole suggestedRole;
+
+dialect  "mvel"
+
+rule "Suggest Manager Role"
+    when
+        Applicant(experienceInYears > 10)
+        Applicant(currentSalary > 1000000 && currentSalary <= 2500000)
+    then
+        suggestedRole.setRole("Manager");
+end
+
+rule "Suggest Senior developer Role"
+    when
+        Applicant(experienceInYears > 5 && experienceInYears <= 10)
+        Applicant(currentSalary > 500000 && currentSalary <= 1500000)
+    then
+        suggestedRole.setRole("Senior developer");
+end
+
+rule "Suggest Developer Role"
+    when
+        Applicant(experienceInYears > 0 && experienceInYears <= 5)
+        Applicant(currentSalary > 200000 && currentSalary <= 1000000)
+    then
+        suggestedRole.setRole("Developer");
+end

spring-drools/src/test/java/com/baeldung/spring/drools/service/ApplicantServiceIntegrationTest.java

@@ -0,0 +1,52 @@
+package com.baeldung.spring.drools.service;
+
+import com.baeldung.spring.drools.Application;
+import com.baeldung.spring.drools.DroolConfiguration;
+import com.baeldung.spring.drools.model.Applicant;
+import com.baeldung.spring.drools.model.SuggestedRole;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import static junit.framework.Assert.assertNull;
+import static junit.framework.TestCase.assertEquals;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = {DroolConfiguration.class})
+public class ApplicantServiceIntegrationTest {
+
+    @Autowired
+    ApplicantService applicantService;
+
+    @Test
+    public void whenCriteriaMatching_ThenSuggestManagerRole(){
+        Applicant applicant=new Applicant("Davis",37,1600000.0,11);
+        SuggestedRole suggestedRole=new SuggestedRole();
+        applicantService.suggestARoleForApplicant(applicant,suggestedRole);
+        assertEquals("Manager",suggestedRole.getRole());
+    }
+
+    @Test
+    public void whenCriteriaMatching_ThenSuggestSeniorDeveloperRole(){
+        Applicant applicant=new Applicant("John",37,1200000.0,8);
+        SuggestedRole suggestedRole=new SuggestedRole();
+        applicantService.suggestARoleForApplicant(applicant,suggestedRole);
+        assertEquals("Senior developer",suggestedRole.getRole());
+    }
+    @Test
+    public void whenCriteriaMatching_ThenSuggestDeveloperRole(){
+        Applicant applicant=new Applicant("Davis",37,800000.0,3);
+        SuggestedRole suggestedRole=new SuggestedRole();
+        applicantService.suggestARoleForApplicant(applicant,suggestedRole);
+        assertEquals("Developer",suggestedRole.getRole());
+    }
+    @Test
+    public void whenCriteriaNotMatching_ThenNoRole(){
+        Applicant applicant=new Applicant("John",37,1200000.0,5);
+        SuggestedRole suggestedRole=new SuggestedRole();
+        applicantService.suggestARoleForApplicant(applicant,suggestedRole);
+        assertNull(suggestedRole.getRole());
+    }
+}

spring-drools/src/test/java/com/baeldung/spring/drools/service/ProductServiceIntegrationTest.java

@@ -0,0 +1,34 @@
+package com.baeldung.spring.drools.service;
+
+import com.baeldung.spring.drools.Application;
+import com.baeldung.spring.drools.DroolConfiguration;
+import com.baeldung.spring.drools.model.Product;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import static junit.framework.TestCase.assertEquals;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = {DroolConfiguration.class})
+public class ProductServiceIntegrationTest {
+
+    @Autowired
+    ProductService productService;
+
+    @Test
+    public void whenProductTypeElectronic_ThenLabelBarcode(){
+        Product product=new Product("Microwave","Electronic");
+        product=productService.applyLabelToProduct(product);
+        assertEquals("BarCode",product.getLabel());
+    }
+
+    @Test
+    public void whenProductTypeBook_ThenLabelIsbn(){
+        Product product=new Product("AutoBiography","Book");
+        product=productService.applyLabelToProduct(product);
+        assertEquals("ISBN",product.getLabel());
+    }
+}