Throw error to calling method!
I have a thread class and in the run method I am making a call to a web service, this call is in a try catch
try {
// Make webs service call
}
catch (Ex开发者_JS百科ception e) {
throw e;
}
Eclipse doesn't like this!
Basically I want to throw this error to the calling method and deal with it there?
If you throw a checked exception, the exception must be handled either with try/catch or declaring it as thrown in the method signature. See the exceptions tutorial; particularly the part about The Three Kinds of Exceptions.
Yep java.lang.Exception
is checked, so you can't throw it (as Runnable.run does not declare any Exceptions in its throws clause; it doesn't have a throws clause). You could only throw RunTimeExceptions. You'll have to handle the Checked Exceptions - that's what Java is forcing you to do. One approach is to convert the Checked Exception into a RunTimeException so you can throw it. But don't forget this is a separate thread, so watch your handling logic.
public class ThreadFun implements Runnable {
public void run() {
// LEGAL
try {
} catch (RuntimeException e) {
throw e;
}
// NOT LEGAL
try {
} catch (Exception e) {
throw e;
}
}
}
That is because you are overriding run()
and overriding won't allow you to declare broader exception to be thrown. You can wrap it up in RuntimeException
.
Do it something like
new Thread(new Runnable() {
public void run() {
try{
//your code
}catch(Exception ex){
throw new RuntimeException(ex);//or appropriate RuntimeException
}
}
}).start();
}
Instead of catching the exception, add throws Exception
to the method signature. This will force the calling method to catch the exception instead.
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