How to convert a StackTraceElement[] to a String?

Question

Thread.getStackTrace() returns StackTraceElement[]. How can I convert this to a String with the same format as Exception.printStackTrace() returns?

To clarify: I don't have an exception, only a thread. I want to display the thread's stack trace using the same format as exception stack traces.

• Gili: @Andreas Obviously I did. The format looks nothing like the desired result. Do you want me to mention this explicitly in the question?
• Andreas: The format of StackTraceElement.toString() looks exactly like the each entry of printStackTrace(), following the at.
• Gili: @Andreas You're right. I had missed this. I marked your answer as accepted.

Answer 1

It is super easy, you just have to print them, with whatever prefix you want.

To print same as printStackTrace(), the prefix would be "\tat ".

Proof

// Show printStackTrace() output
new RuntimeException().printStackTrace(System.out);
// Similar output using getStackTrace()
StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
System.out.println("getStackTrace()");
for (int i = 1; i < stackTrace.length; i++)
 System.out.println("\tat " + stackTrace[i]);

Output

java.lang.RuntimeException
 at Test.main(Test.java:5)
getStackTrace()
 at Test.main(Test.java:8)

Note how for loop skipped index 0, since that is the stack frame for getStackTrace() itself.

• Gili: I wanted to get back a String, not output to stdout, but I get your point. Good catch piggybacking on StackTraceElement.toString(). I didn't realize this had the correct format.