Java Error Catching Issue

Question

I have a try/catch thing set up where it will catch all exceptions and then display the error.

Here is my code:

try {
    //CODE THAT COULD ERROR HERE
} catch (final Exception e) {
    System.err.println("Unexpected error: " + e.getStackTrace()[0]);
}

The above code gives me the LAST class that had the error. How do I detect the LAST class of MY PROGRAM that had the error?

Example Output: "Unexpected error: package.ClassName.method(ClassName.java:46)"

I want it to output the line of my program that had the error, not the line of a built-in java class that error-ed because of my program.

Answer 1

e.printStackTrace()

might make you happier. Or print the top of the array of stack trace entries available from the appropriate method.

http://docs.oracle.com/javase/6/docs/api/java/lang/Throwable.html#getStackTrace()

returns them. The first one is what you are asking for.

Answer 2

You can use getStackTrace to get an array of StackTraceElement instances, and filter that based on your package and/or class names (using getClassName for each element, which gives you the fully-qualified class name for that stack trace frame). That would let you winnow it down to your code rather than the JDK class the exception originated in.

Answer 3

        try {
            //error producing code
        } catch (Exception e) {
            for (StackTraceElement s : e.getStackTrace()) {
                if (!s.getClassName().startsWith("java.")) {
                    System.out.println("file name: " + s.getFileName());
                    System.out.println("class name: " + s.getClassName());
                    System.out.println("method name: " + s.getMethodName());
                    System.out.println("line number: " + s.getLineNumber());
                    System.out.println();
                    //break; // will be the highest non java package...
                }
            }
        }

You of course could switch it to be package specific so if (s.getClassName().startsWith("com.company")) { so it wont return for a third party library or something in the sun package or other non java package.