打印全部异常堆栈、ExceptionUtils.getFullStackTrace这样最快

//打印全部异常堆栈
public class ExceptionUtils {
  public static void main(String[] args) {
    try {
      int a=1/0;
    } catch (Exception e) {
      e.printStackTrace();
      String fullStackTrace = org.apache.commons.lang.exception.ExceptionUtils.getFullStackTrace(e);
      System.out.println(fullStackTrace);
    }
  }
}

 /**
     * <p>A way to get the entire nested stack-trace of an throwable.</p>
     *
     * <p>The result of this method is highly dependent on the JDK version
     * and whether the exceptions override printStackTrace or not.</p>
     *
     * @param throwable  the <code>Throwable</code> to be examined
     * @return the nested stack trace, with the root cause first
     * @since 2.0
     */
    public static String getFullStackTrace(Throwable throwable) {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw, true);
        Throwable[] ts = getThrowables(throwable);
        for (int i = 0; i < ts.length; i++) {
            ts[i].printStackTrace(pw);
            if (isNestedThrowable(ts[i])) {
                break;
            }
        }
        return sw.getBuffer().toString();
    }

//另一种方式
public static String exception2String(Exception ex){
    String exceptionMessage = "";
    if (ex != null) {
      StringWriter sw = new StringWriter();
      PrintWriter pw = new PrintWriter(sw);
      try {
        ex.printStackTrace(pw);
        exceptionMessage = sw.toString();
      } finally {
        try {
          sw.close();
          pw.close(); 
        } catch (Exception e) {
        }
      }
    }
    return exceptionMessage;
  }