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  • Java web错误汇总

    环境:

    • 电脑:win 10

    • IDE:

      • Eclipse Java EE IDE for Web Developers.
      • Version: Luna Service Release 2 (4.4.2)
      • Build id: 20150219-0600
    1、properties读取配置文件,报空指针异常错误
    • 错误信息:
    java.lang.NullPointerException
    	at java.util.Properties$LineReader.readLine(Properties.java:434)
    	at java.util.Properties.load0(Properties.java:353)
    	at java.util.Properties.load(Properties.java:341)
    	at com.javasm.util.JdbcUtils.getConnection(JdbcUtils.java:20)
    	at com.javasm.util.JdbcUtils.tetsConnection(JdbcUtils.java:37)
    	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	at java.lang.reflect.Method.invoke(Method.java:497)
    	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    	at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    	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:459)
    	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
    	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
    	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
    
    
    • 源码:
    InputStream inputStream = JdbcUtils.class.getClassLoader()
    				.getResourceAsStream("dbconfig.properties");
    		Properties properties = new Properties();
    
    • 原因:配置文件路径书写错误!!!

    • 修改后的路径:

    InputStream inputStream = JdbcUtils.class.getClassLoader()
    				.getResourceAsStream("com/javasm/util/dbconfig.properties");
    		Properties properties = new Properties();
    
    • 注意:配置文件直接放在项目根目录下 无法正确读取,只有放在对应的目录下才可以
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  • 原文地址:https://www.cnblogs.com/caoleiCoding/p/9028910.html
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