GNDMSVerInfo.java

package de.zib.gndms;

/*
 * Copyright 2008-2011 Zuse Institute Berlin (ZIB)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */



import org.jetbrains.annotations.NotNull;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;


/**
 * A GNDMSVerInfo instance returns a String, containg informations about a specific version of the GNDMSystem.
 * It uses text-files located at {@code META-INF/} .
 *
 * @author  try ste fan pla nti kow zib
 * @version $Id$
 *
 *          User: stepn Date: 09.12.2008 Time: 18:01:03
 */
public class GNDMSVerInfo {

    /**
     * Reads a text file and returns it as a a String.
     * The file must be located in the folder {@code META-INF} and start with the name {@code GNDMS-}
     * @param infoTag the tag of the text file. This means the file must have the name {@code GNDMS-%infoTag}
     * @return the text of the specified text file
     */
	@SuppressWarnings({ "HardcodedFileSeparator", "NestedAssignment" })
	private @NotNull String readInfo(@NotNull String infoTag) {
		final String resName = "META-INF/GNDMS-" + infoTag;
		final InputStream in = getClass().getClassLoader().getResourceAsStream(resName);
		try {
			try {
				final InputStreamReader inReader = new InputStreamReader(in);
				try {
					final BufferedReader reader = new BufferedReader(inReader);
					try {
						StringBuilder result = new StringBuilder(8);
						String line;
						/* intentionally kills all newlines */
						while ((line = reader.readLine()) != null)
							result.append(line);
						return result.toString().trim();
					}
					finally { reader.close(); }
				}
				finally { inReader.close(); }
			}
			finally { in.close(); }
		}
		catch (NullPointerException npe) {
			return "<none>";
		}
		catch (IOException e) {
			return "<none>";
		}
	}

    /**
     * Returns the content of the {@code GNDMS-BUILD-INFO} file, containing information about the build version.
     *
     * @return the content of the {@code GNDMS-BUILD-INFO} file, containing information about the build version.
     */
	public String readBuildInfo() {
		return readInfo("BUILD-INFO");
	}

    /**
     * Returns the content of the {@code GNDMS-RELEASE} file, containing information about the release version.
     *
     * @return the content of the {@code GNDMS-RELEASE} file, containing information about the release version.
     */
	public String readRelease() {
		return readInfo("RELEASE");
	}
}