/*
 * #%L
 * ImageJ software for multidimensional image processing and analysis.
 * %%
 * Copyright (C) 2009 - 2012 Board of Regents of the University of
 * Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
 * Institute of Molecular Cell Biology and Genetics.
 * %%
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * The views and conclusions contained in the software and documentation are
 * those of the authors and should not be interpreted as representing official
 * policies, either expressed or implied, of any organization.
 * #L%
 */

package imagej.core.plugins.debug;

import imagej.ext.module.ItemIO;
import imagej.ext.plugin.ImageJPlugin;
import imagej.ext.plugin.Parameter;
import imagej.ext.plugin.Plugin;

import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Properties;
import java.util.regex.Pattern;

/**
 * Dumps Java system properties.
 * 
 * @author Curtis Rueden
 */
@Plugin(menuPath = "Plugins>Debug>System Properties", headless = true)
public class SysProps implements ImageJPlugin {

	// -- Parameters --

	@Parameter(label = "System Properties", type = ItemIO.OUTPUT)
	private String properties;

	// -- Runnable methods --

	@Override
	public void run() {
		final StringBuilder sb = new StringBuilder();
		final String nl = System.getProperty("line.separator");

		final Properties props = System.getProperties();
		final ArrayList<String> propKeys =
			new ArrayList<String>(props.stringPropertyNames());
		Collections.sort(propKeys);

		for (final String key : propKeys) {
			if (key == null) continue;
			final String value = props.getProperty(key);
			if (value == null) continue;

			if (key.endsWith(".dirs") || key.endsWith(".path")) {
				// split path and display values as a list
				final String[] dirs = value.split(Pattern.quote(File.pathSeparator));
				sb.append(key + " = {" + nl);
				for (final String dir : dirs) {
					sb.append("\t" + dir + nl);
				}
				sb.append("}" + nl);
			}
			else {
				// display a single key/value pair
				sb.append(key + " = " + props.get(key) + nl);
			}
		}
		properties = sb.toString();
	}

	// -- SysProps methods --

	public String getProperties() {
		return properties;
	}

}

Add a plugin that dumps Java system properties