ExceptionUtil.java

/*
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package org.glassfish.installer.util;

import java.util.ArrayList;

/**
 * Utility class to scan through exception stack and return the exception
 * at the bottom thereby identifying the root cause of the problem.
 * Code reused from ExceptionUtil
 * @author sathyan
 */
public class ExceptionUtil {

    /**
     * @param start    the Exception to traverse
     * @return         a Throwable[] or an Exception[] as appropriate
     */
    public static Throwable[] getCauses(Throwable start) {

        ArrayList list = new ArrayList();

        boolean haveNonException = false;

        Throwable t = start;
        while (t != null) {
            list.add(t);

            if (!(t instanceof Exception)) {
                haveNonException = true;
            }

            Throwable temp = t.getCause();
            if (temp == null) {
                break;
            }
            t = temp;
        }

        Throwable[] results = haveNonException
                ? new Throwable[list.size()] : new Exception[list.size()];

        list.toArray(results);

        return (results);
    }

    /**
     * Get the root cause of exception.
     * @param e        the Exception to dig into
     * @return         the original Throwable that started the problem
     */
    public static Throwable getRootCause(Throwable e) {
        Throwable[] causes = getCauses(e);

        return (causes[causes.length - 1]);
    }
}