jasper出现NullPointException。急
我写了一个a.jasper文件,在IReport中通过JDBC直接连接可以出来数据.但是放到项目中就出现NullPointException。如下：
java.lang.NullPointerException
at net.sf.jasperreports.engine.JRPropertiesMap.readObject(JRPropertiesMap.java:185)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:946)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1809)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1719)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1908)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1832)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1719)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1634)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1908)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1832)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1719)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1908)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1832)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1719)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:348)
at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:88)
at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:64)
at com.newheight.webapp.action.report.ReportAction.generateReport(ReportAction.java:145)
at com.newheight.webapp.action.report.ReportAction.exportHtml(ReportAction.java:118)
at com.newheight.webapp.action.report.ReportAction$$FastClassByCGLIB$$5d99d159.invoke(<generated>)
at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:149)
at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:700)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:77)
at com.newheight.aop.BackendAccessLogAspect.securityAccess(BackendAccessLogAspect.java:56)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:627)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:616)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:64)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:160)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:77)
at com.newheight.aop.ActionAccessAspect.securityAccess(ActionAccessAspect.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:627)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:616)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:64)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:160)
at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:77)
at com.newheight.aop.ExceptionHandlerAspect.exceptionHandler(ExceptionHandlerAspect.java:52)
at sun.reflect.GeneratedMethodAccessor71.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:627)
at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:616)
at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:64)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:90)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.Cglib2AopProxy$DynamicAdvisedInterceptor.intercept(Cglib2AopProxy.java:635)
at com.newheight.webapp.action.report.ReportAction$$EnhancerByCGLIB$$bcfe711c.exportHtml(<generated>)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
[解决办法]
在这行com.newheight.webapp.action.report.ReportAction.generateReport(ReportAction.java:145) 设个断点 看看是那个报null了，这样问题就容易找到
[解决办法]
java.lang.ClassCastException: java.util.Date
类型转换不对，该是在你这行代码出了问题吧com.newheight.webapp.action.report.ReportAction.generateReport(ReportAction.java:166)
[解决办法]
dug查找原因...
[解决办法]
日期类型请注意java.sql.Date ....java.util.Date
