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POSpring Data Neo4j Sample program error
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I am creating a small application for getting to know Neo4j and Spring Data Neo4j. But I got NullPointerException always. Hence I used one of the most <a href="https://github.com/SpringSource/spring-data-neo4j/tree/master/spring-data-neo4j-examples/hello-worlds" rel="nofollow">simple examples</a> of Spring Data Neo4j and have updated the test file with main() from JUnit. My Test File is as follows: <pre><code>package com.spring.nosql.neo4j.worldTest; import java.util.Collection; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.graph.neo4j.template.Neo4jTemplate; import org.springframework.test.annotation.Rollback; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.transaction.BeforeTransaction; import org.springframework.transaction.annotation.Transactional; /** * @author srahul07 * */ @ContextConfiguration(locations = "classpath:neo4jBeans.xml") @Transactional public class Main { @Autowired private GalaxyService galaxyService; @Autowired private Neo4jTemplate template; @Rollback(false) @BeforeTransaction public void shouldAllowDirectWorldCreation() { // assertEquals(0, galaxyService.getNumberOfWorlds()); System.out.println("Number of Worlds: " + galaxyService.getNumberOfWorlds()); World myWorld = galaxyService.createWorld("mine", 0); System.out.println("Number of Worlds: " + galaxyService.getNumberOfWorlds()); // assertEquals(1, galaxyService.getNumberOfWorlds()); Iterable<World> foundWorlds = galaxyService.getAllWorlds(); World mine = foundWorlds.iterator().next(); System.out.println("Number of Worlds: " + myWorld.getName() + " Name: " + mine.getName()); // assertEquals(myWorld.getName(), mine.getName()); } public void shouldHaveCorrectNumberOfWorlds() { galaxyService.makeSomeWorlds(); System.out.println("Number of Worlds: " + galaxyService.getNumberOfWorlds()); // assertEquals(13, galaxyService.getNumberOfWorlds()); } public void shouldFindWorldsById() { galaxyService.makeSomeWorlds(); for (World world : galaxyService.getAllWorlds()) { World foundWorld = galaxyService.findWorldById(world.getId()); System.out.println("Found World: " + foundWorld); // assertNotNull(foundWorld); } } public void shouldFindWorldsByName() { galaxyService.makeSomeWorlds(); for (World world : galaxyService.getAllWorlds()) { World foundWorld = galaxyService.findWorldByName(world.getName()); System.out.println("Found Worlds: " + foundWorld); // assertNotNull(foundWorld); } } public void shouldReachMarsFromEarth() { galaxyService.makeSomeWorlds(); World earth = galaxyService.findWorldByName("Earth"); World mars = galaxyService.findWorldByName("Mars"); System.out.println("Mars Rechable from Earth: " + mars.canBeReachedFrom(earth)); System.out.println("Earth Reachable from Mars: " + earth.canBeReachedFrom(mars)); // assertTrue(mars.canBeReachedFrom(earth)); // assertTrue(earth.canBeReachedFrom(mars)); } public void shouldFindAllWorlds() { Collection<World> madeWorlds = galaxyService.makeSomeWorlds(); Iterable<World> foundWorlds = galaxyService.getAllWorlds(); int countOfFoundWorlds = 0; for (World foundWorld : foundWorlds) { System.out.println("Worlds Contains: " + madeWorlds.contains(foundWorld)); // assertTrue(madeWorlds.contains(foundWorld)); countOfFoundWorlds++; } System.out.println("World's Size: " + madeWorlds.size() + " Count of Found Worlds: " + countOfFoundWorlds); // assertEquals(madeWorlds.size(), countOfFoundWorlds); } @SuppressWarnings("unchecked") public void shouldFindWorldsWith1Moon() { galaxyService.makeSomeWorlds(); for (World worldWithOneMoon : galaxyService.findAllByNumberOfMoons(1)) { System.out.println("World With One Moon: " + worldWithOneMoon.getName()); System.out.println("World With One Moon is Earth?: " + worldWithOneMoon.getName().contains("Earth")); System.out.println("World With One Moon is Earth?: " + worldWithOneMoon.getName().contains("Midgard")); /* * assertThat( worldWithOneMoon.getName(), * is(anyOf(containsString("Earth"), containsString("Midgard")))); */ } } public void shouldNotFindKrypton() { galaxyService.makeSomeWorlds(); World krypton = galaxyService.findWorldByName("Krypton"); System.out.println("World is Krypton: " + krypton.getName().isEmpty()); // assertNull(krypton); } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub try { Main mainTest = new Main(); mainTest.shouldHaveCorrectNumberOfWorlds(); mainTest.shouldAllowDirectWorldCreation(); mainTest.shouldFindAllWorlds(); mainTest.shouldFindWorldsById(); mainTest.shouldFindWorldsByName(); mainTest.shouldFindWorldsWith1Moon(); mainTest.shouldNotFindKrypton(); mainTest.shouldReachMarsFromEarth(); } catch (Exception ae) { ae.printStackTrace(); } } } </code></pre> My Spring context configurations is as follows: <pre><code><?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:neo4j="http://www.springframework.org/schema/data/neo4j" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/data/neo4j http://www.springframework.org/schema/data/neo4j/spring-neo4j.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <context:spring-configured/> <context:annotation-config/> <context:component-scan base-package="com.spring.nosql.neo4j.worldTest" /> <neo4j:config storeDirectory="target/neo4j-db"/> <neo4j:repositories base-package="com.spring.nosql.neo4j.worldTest"/> </beans> </code></pre> Whenever I run my test code, I get following Error: <pre><code>java.lang.NullPointerException at com.spring.nosql.neo4j.worldTest.Main.shouldHaveCorrectNumberOfWorlds(Main.java:48) at com.spring.nosql.neo4j.worldTest.Main.main(Main.java:141) </code></pre> Is there anything I missed in my configurations? Or is there anything extra needed here? As far as I understood, the Neo4j will create graph database in "target/neo4j-db". Also, since my machine is Ubuntu I have installed debian package of Neo4j on my machine. So I also tried to use it via using REST API. So for this I made following configurations to my spring context file: <pre><code><?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:neo4j="http://www.springframework.org/schema/data/neo4j" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/data/neo4j http://www.springframework.org/schema/data/neo4j/spring-neo4j.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <context:spring-configured/> <context:annotation-config/> <context:component-scan base-package="com.spring.nosql.neo4j.worldTest" /> <neo4j:repositories base-package="com.spring.nosql.neo4j.worldTest"/> <neo4j:config graphDatabaseService="graphDatabaseService"/> <bean id="graphDatabaseService" class="org.springframework.data.neo4j.rest.SpringRestGraphDatabase"> <constructor-arg index="0" value="http://localhost:7474/db/data" /> <constructor-arg index="1" value="" /> <constructor-arg index="2" value="" /> </bean> </code></pre> But still I am getting same Exception. FYI: I have included Spring, Spring Data Neo4j and Neo4j libraries to my buildpath in Eclipse. EDIT: Well since there was no response on this, I tried the same example as it is with JUnit Test case as per provided in examples <a href="https://github.com/SpringSource/spring-data-neo4j/tree/master/spring-data-neo4j-examples/hello-worlds" rel="nofollow">here</a>: In my JUnit test case I got following errors on each of the methods: <pre><code>java.lang.NoClassDefFoundError: org/neo4j/cypherdsl/grammar/Execute at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2442) at java.lang.Class.getDeclaredMethods(Class.java:1808) at org.springframework.util.ReflectionUtils.findMethod(ReflectionUtils.java:154) at org.springframework.util.ClassUtils.getMostSpecificMethod(ClassUtils.java:730) at org.springframework.data.repository.core.support.TransactionalRepositoryProxyPostProcessor$AbstractFallbackTransactionAttributeSource.computeTransactionAttribute(TransactionalRepositoryProxyPostProcessor.java:326) at org.springframework.data.repository.core.support.TransactionalRepositoryProxyPostProcessor$AbstractFallbackTransactionAttributeSource.getTransactionAttribute(TransactionalRepositoryProxyPostProcessor.java:282) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:99) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:155) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) at $Proxy31.count(Unknown Source) at com.spring.nosql.neo4j.worldTest.GalaxyService.getNumberOfWorlds(GalaxyService.java:16) at com.spring.nosql.neo4j.worldTest.GalaxyServiceTest.shouldAllowDirectWorldCreation(GalaxyServiceTest.java:40) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:601) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20) at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74) at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83) at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71) at org.junit.runners.ParentRunner.run(ParentRunner.java:300) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197) Caused by: java.lang.ClassNotFoundException: org.neo4j.cypherdsl.grammar.Execute at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) ... 43 more </code></pre> This says that the class named: org/neo4j/cypherdsl/grammar/Execute is not found or missing. This does mean that I am missing one of the library, but the Neo4j Library shows the package named <code>neo4j-cypher-1.8.jar</code>. But in this I have not found <code>cypherdsl</code>. Edit2: Well finally it worked with JUnit but not with the <code>public static void main()</code> <code>[psvm]</code>. I was missing one library called <code>cypherdsl</code> which can be downloaded from <a href="http://m2.neo4j.org/content/repositories/releases/org/neo4j/neo4j-cypher-dsl/1.8/neo4j-cypher-dsl-1.8.jar" rel="nofollow">here</a>. But why it does not work when I go for <code>psvm</code>?
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Spring Data Neo4j Sample program error
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