Initial release

2002-07-25 05:58:28 +00:00 · 2002-07-25 05:58:28 +00:00 · ae6d735cce
commit ae6d735cce
1 changed files with 112 additions and 0 deletions
--- a/Classpath.java
+++ b/Classpath.java
@ -0,0 +1,112 @@
+/*
+ * @(#)Classpath.java
+ *
+ * Copyright (C) 2001 by Erik C. Thauvin (erik@thauvin.net)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * A copy of the GNU General Public License can be obtained by
+ * visting the Free Software Foundation Web site at:
+ *
+ *		<http://www.gnu.org/copyleft/gpl.html>
+ *
+ * or by writting to:
+ *
+ *		Free Software Foundation, Inc.
+ *		59 Temple Place - Suite 330
+ *		Boston, MA 02111-1307, USA.
+ *
+ * $Id$
+ */
+import java.io.*;
+import java.util.StringTokenizer;
+
+/**
+ * The Classpath class demonstrates how to check for the presence of a given
+ * library in the system class path.
+ *
+ * @author Erik C. Thauvin
+ * @created September 7, 2001
+ */
+public class Classpath extends java.lang.Object
+{
+
+	/**
+	 * Returns true if the given library is included the system class path, and
+	 * actually exists on disk. Returns false otherwise.
+	 *
+	 * @param libName The name of the library
+	 * @return true or false.
+	 */
+	public static boolean isLibInClassPath(String libName)
+	{
+		// Get the class path
+		String classPath =
+				System.getProperty("java.class.path", ".").toLowerCase();
+
+		// Get the library name (e.g.: "\tools.jar")
+		String lib = (File.separator + libName.toLowerCase());
+
+		// Tokenize the class path using the path separator
+		StringTokenizer st =
+				new StringTokenizer(classPath, File.pathSeparator);
+
+		String libPath;
+		File filePath;
+
+		// Loop thru the class path entries
+		while (st.hasMoreTokens())
+		{
+			// Get the current class path entry
+			libPath = st.nextToken();
+
+			// Does it contain our library?
+			if (libPath.endsWith(lib))
+			{
+				filePath = new File(libPath);
+
+				// Does the file actually exists?
+				if (filePath.exists())
+				{
+					return true;
+				}
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * The main program for the Classpath class.
+	 *
+	 * @param args The command line arguments.
+	 */
+	public static void main(String[] args)
+	{
+		if (args.length == 1)
+		{
+			System.out.print("The \"" + args[0] + "\" library was ");
+
+			if (!Classpath.isLibInClassPath(args[0]))
+			{
+				System.out.print("NOT ");
+			}
+
+			System.out.println("found in the system class path.");
+		}
+		else
+		{
+			// e.g.: java -cp .;C:\jdk1.3\lib\tools.jar Classpath tools.jar
+			System.err.println("Usage: java Classpath <library name>");
+		}
+	}
+}
+