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EasyStream is a small set of utilities for dealing with streams (InputStreams and OutputStreams). The aim is to ease the use of pipes when they're required. Main features are: * "Convert" an OutputStream to an InputStream. * Count the number of bytes read or wrote to a given stream. * While reading the data from an InputStream copy it to a supplied OutputStream. * Read the content of an InputStream multiple times or seek to a definite position

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package com.gc.iotools.stream.utils;
/*
 * Copyright (c) 2008, 2015 Gabriele Contini. This source code is released
 * under the BSD License.
 */

/**
 * Utilities for logging.
 *
 * @author dvd.smnt
 * @since 1.0.9
 * @version $Id: LogUtils.java 576 2015-03-28 00:03:33Z gcontini $
 */
public final class LogUtils {
	/**
	 * Returns the caller of the class passed as an argument. Useful for
	 * logging.
	 *
	 * @param clazz
	 *            The current class
	 * @return The class name up one level in the stack.
	 */
	public static String getCaller(final Class clazz) {
		return getCaller(clazz, 1);
	}

	/**
	 * Returns the caller stack of the class passed as an argument. Useful for
	 * logging.
	 *
	 * @since 1.2.6
	 * @param nframes
	 *            Number of stack frames to log out.
	 * @param me
	 *            The current class
	 * @return All the class names, methods and line numbers up nframes level
	 *         in the stack.
	 */
	public static String getCaller(final Class me, final int nframes) {
		final StackTraceElement[] stes = Thread.currentThread()
				.getStackTrace();
		final int stackTracePosition = getCallerPosition(me, stes);
		String result;
		if (stackTracePosition >= stes.length - 1) {
			result = "class [" + me.getName()
					+ "] not found in caller's stack trace.";
		} else {
			final StringBuffer resBuffer = new StringBuffer();
			for (int i = stackTracePosition; (i < stes.length)
					&& (i < (stackTracePosition + nframes)); i++) {
				final StackTraceElement stelement = stes[i];
				final String className = stelement.getClassName();
				final String simpleClassName = className.substring(className
						.lastIndexOf('.') + 1);
				if (resBuffer.length() > 0) {
					resBuffer.append(" / ");
				}
				resBuffer.append(simpleClassName + "."
						+ stelement.getMethodName() + ":"
						+ stelement.getLineNumber());
			}
			result = resBuffer.toString();
		}
		return result;
	}

	private static int getCallerPosition(final Class me,
			final StackTraceElement[] stes) {
		boolean foundCaller = false;
		boolean foundClazz = false;
		int stackTracePosition = 0;
		for (; (stackTracePosition < stes.length) && !foundCaller; stackTracePosition++) {
			final StackTraceElement stackTraceElement = stes[stackTracePosition];
			foundClazz |= me.getName().equals(
					stackTraceElement.getClassName());
			foundCaller |= foundClazz
					&& !me.getName().equals(stackTraceElement.getClassName());
		}
		stackTracePosition--;
		return stackTracePosition;
	}

	/*
	 * Utility class: shouldn't be instantiated.
	 */
	private LogUtils() {
		// utility class.
	}
}