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Java 如何绕过空指针异常?#JPF_Java_Nullpointerexception_Jpf - Fatal编程技术网

Java 如何绕过空指针异常?#JPF

Java 如何绕过空指针异常?#JPF,java,nullpointerexception,jpf,Java,Nullpointerexception,Jpf,我试图运行JPF,但遇到以下空指针异常 java.lang.NullPointerException at gov.nasa.jpf.vm.ThreadInfo$StackTraceElement.createJPFStackTraceElement(ThreadInfo.java:1671) 对应的代码为: int createJPFStackTraceElement() { if (ignore) { return MJIEnv.NULL; } else {

我试图运行JPF,但遇到以下空指针异常

java.lang.NullPointerException at gov.nasa.jpf.vm.ThreadInfo$StackTraceElement.createJPFStackTraceElement(ThreadInfo.java:1671)
对应的代码为:

int createJPFStackTraceElement() {
    if (ignore) {
        return MJIEnv.NULL;
    } else {
        Heap heap = vm.getHeap();
        ClassInfo ci = ClassLoaderInfo.getSystemResolvedClassInfo("java.lang.StackTraceElement");
        ElementInfo ei = heap.newObject(ci, ThreadInfo.this);

        ei.setReferenceField("clsName", heap.newString(clsName, ThreadInfo.this).getObjectRef());
        ei.setReferenceField("mthName", heap.newString(mthName, ThreadInfo.this).getObjectRef());
        ei.setReferenceField("fileName", heap.newString(fileName, ThreadInfo.this).getObjectRef());  //line 1671
        ei.setIntField("line", line);

        return ei.getObjectRef();
    }
}
有两种方法

  • 您的代码应该包含null检查,所以首先它将检查值是否为null,然后决定代码段是否应该执行
  • 或者您可以使用try catch block