From: Erik Brakkee <erik@brakkee.org>
Date: Tue, 22 Jun 2010 20:37:02 +0000 (+0000)
Subject: (no commit message)
X-Git-Tag: wamblee-utils-0.7~403
X-Git-Url: http://wamblee.org/gitweb/?a=commitdiff_plain;h=da0699d61503e0fcd21f41bd05aa8a2d993c3010;p=utils

---

diff --git a/support/general/src/main/java/org/wamblee/classloading/ClassLoaderUtils.java b/support/general/src/main/java/org/wamblee/classloading/ClassLoaderUtils.java
new file mode 100644
index 00000000..65c70456
--- /dev/null
+++ b/support/general/src/main/java/org/wamblee/classloading/ClassLoaderUtils.java
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2005-2010 the original author or authors.
+ * 
+ * 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.
+ */ 
+package org.wamblee.classloading;
+
+import java.io.File;
+import java.io.IOException;
+
+import java.lang.reflect.Method;
+
+import java.net.URL;
+import java.net.URLClassLoader;
+
+/**
+ * Utility for working with the class loader. Based on the ClassPathHacker
+ * example found on the internet.
+ */
+public class ClassLoaderUtils {
+    // No logging in this class to keep the required class libraries
+    // limited to the standard java classes. This allows use of the
+    // utilities in an environment with a very limited classpath.
+    private static final String JAR_SUFFIX = ".jar";
+
+    /**
+     * Adds all jars in the given directory to the class path.
+     * 
+     * @param aDirectory
+     *            Directory.
+     * @throws IOException
+     */
+    public static void addJarsInDirectory(File aDirectory) throws IOException {
+        System.out.println("directory '" + aDirectory + "'");
+
+        for (File aFile : aDirectory.listFiles()) {
+            System.out
+                .println("Considering '" + aFile.getCanonicalPath() + "'");
+
+            if (aFile.getName().toLowerCase().endsWith(JAR_SUFFIX)) {
+                System.out.println("Adding '" + aFile.getCanonicalPath() +
+                    "' to classpath.");
+                addFile(aFile);
+            }
+        }
+    }
+
+    /**
+     * Adds a file to the classpath.
+     * 
+     * @param aFilename
+     *            Filename to add.
+     * @throws IOException
+     */
+    public static void addFile(String aFilename) throws IOException {
+        File f = new File(aFilename);
+        addFile(f);
+    }
+
+    /**
+     * Adds a file to the classpath.
+     * 
+     * @param aFile
+     *            File to add.
+     * @throws IOException
+     */
+    public static void addFile(File aFile) throws IOException {
+        addURL(aFile.toURL());
+    }
+
+    /**
+     * Adds a url to the classpath.
+     * 
+     * @param aUrl
+     *            Url to add.
+     * @throws IOException
+     */
+    public static void addURL(URL aUrl) throws IOException {
+        URLClassLoader sysloader = (URLClassLoader) ClassLoader
+            .getSystemClassLoader();
+        Class sysclass = URLClassLoader.class;
+
+        try {
+            Method method = sysclass.getDeclaredMethod("addURL",
+                new Class[] { URL.class });
+            method.setAccessible(true);
+            method.invoke(sysloader, new Object[] { aUrl });
+        } catch (Throwable t) {
+            t.printStackTrace();
+            throw new IOException(
+                "Error, could not add URL to system classloader");
+        }
+    }
+}