CtClass.toClass throws an exception with message 'null'
Steps i perform to create dynamic class is as follows:
try
{
classLoader = Class.forName("org.yaddayadda.DynamicClass" + genericType.getName().toLowerCase() + uniqueID);
}
catch (ClassNotFoundException classNotFoundException)
{
}
if (classLoader == null)
{
dynamicClass = pool.get("org.yaddayadda.DynamicClass");
dynamicClass.defrost();
dynamicClass.replaceClassName("org.yaddayadda.DynamicClass","org.yaddayadda.DynamicClass"+ genericType.getName().toLowerCase() + uniqueID);
dynamicClass.defrost();
CtMethod readObject = dynamicClass.getDeclaredMethod("Method1");
CtMethod writeObject = dynamicClass.getDeclaredMethod("Method2");
StringBuffer method1= new StringBuffer();
StringBuffer method2= new StringBuffer();
GenerateDynamicCode.generateCode(genericType, method1, method2);
writeObject.insertAt(1, method1.toString());
readObject.insertAt(1, method2.toString());
//This is where the exception is thrown
classLoader = dynamicClass.toClass();
}
I first try to check if the class already exists in ClassPool
if not then i proceed on to creating a class. Defrost is done for just a fail-safe mechanism. The Exception comes when the method toClass
is called dynamicClass.toClass();
The Exception is as follows
Exception Message: null
Stack Trace:
sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
javassist.ClassPool.toClass2(ClassPool.java:1102)
javassist.ClassPool.toClass(ClassPool.java:1083)
javassist.ClassPool.toCl开发者_C百科ass(ClassPool.java:1032)
javassist.ClassPool.toClass(ClassPool.java:990)
javassist.CtClass.toClass(CtClass.java:1125)
This Class
What is the reason of the above exception and what can be done to avoid it ?
Well i have found a solution, in fact a workaround i.e. i simply call in a loop again defrosting the compiled class and redoing everything i just tried when an exception comes and the loop runs at most 3 times just to be on the safe side
int i = 0;
while (classLoader == null)
{
try
{
if (classLoader == null)
{
dynamicClass = pool.get("org.yaddayadda.DynamicClass");
dynamicClass.defrost();
try
{
dynamicSurrugate = pool.get("org.yaddayadda.DynamicClass" + genericType.getName().toLowerCase() + uniqueID);
dynamicSurrugate.defrost();
}
catch (NotFoundException notFoundException)
{
}
//Everything the same
}
}
catch (Exception exception)
{
classLoader = null;
i++;
}
if (i == 3)
{
throw new Exception("IF failed throw message third time");
}
}
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