test/hotspot/jtreg/vmTestbase/nsk/share/CustomClassLoader.java
changeset 49934 44839fbb20db
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/vmTestbase/nsk/share/CustomClassLoader.java	Mon Apr 30 18:10:24 2018 -0700
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package nsk.share;
+
+import java.io.*;
+
+/**
+ * The <code>CustomClassLoader</code> class is used in <code>ClassUnloader</code>.
+ *
+ * <p>This class loader can load classes and notify <code>ClassUnloader</code>
+ * about own finalization to make sure that all loaded classes have been unloaded.
+ *
+ * <p>By default this class loader loads class from .class file located in directory
+ * specified with <code>setClassPath()</code> method. To use any other technique
+ * of class loading one should implement derived class, which would override
+ * <code>findClass</code> method.
+ *
+ * @see nsk.share.ClassUnloader
+ *
+ * @see #setClassPath(String)
+ * @see #findClass(String)
+ */
+public class CustomClassLoader extends ClassLoader {
+
+    private ClassUnloader classUnloader;
+    protected String classPath;
+
+    /**
+     * Initializes a newly created <code>CustomClassloader</code> object
+     * not yet linked with any <code>ClassUnloader</code> object.
+     *
+     */
+    public CustomClassLoader() {
+        super(CustomClassLoader.class.getClassLoader());
+        this.classUnloader = null;
+    }
+
+    /**
+     * Initializes a newly created <code>CustomClassloader</code> object
+     * linked with specified <code>ClassUnloader</code> object.
+     *
+     * @param classUnloader an instance of <code>ClassUnloader</code>
+     */
+    public CustomClassLoader(ClassUnloader classUnloader) {
+        super(CustomClassLoader.class.getClassLoader());
+        this.classUnloader = classUnloader;
+    }
+
+    /**
+     * Links this class loader with specified <code>ClassUnloader</code> object.
+     *
+     * @param classUnloader an instance of <code>ClassUnloader</code>
+     */
+    public void setClassUnloader(ClassUnloader classUnloader) {
+        this.classUnloader = classUnloader;
+    }
+
+    /**
+     * Specifies path to .class file location.
+     *
+     * @param classPath a path to .class file location
+     */
+    public void setClassPath(String classPath) {
+        this.classPath = classPath;
+    }
+
+    /**
+     * Finds and loads class for specified class name.
+     * This method loads class from .class file located in a directory
+     * previously specified by <code>setClassPath()</code>.
+     *
+     * @param name The name of the class.
+     *
+     * @throws ClassNotFoundException if no .class file found
+     *          for specified class name
+     *
+     * @see #setClassPath(String)
+     */
+    protected synchronized Class findClass(String name) throws ClassNotFoundException {
+        java.nio.file.Path path = ClassFileFinder.findClassFile(name, classPath);
+        if (path == null) {
+            throw new ClassNotFoundException(name);
+        }
+        String classFileName = path.toString();
+
+        FileInputStream in;
+        try {
+            in = new FileInputStream(classFileName);
+            if (in == null) {
+                throw new ClassNotFoundException(classFileName);
+            }
+        } catch (FileNotFoundException e) {
+            throw new ClassNotFoundException(classFileName, e);
+        }
+
+        int len;
+        byte data[];
+        try {
+            len = in.available();
+            data = new byte[len];
+            for (int total = 0; total < data.length; ) {
+                total += in.read(data, total, data.length - total);
+            }
+        } catch (IOException e) {
+            throw new ClassNotFoundException(classFileName, e);
+        } finally {
+            try {
+                in.close();
+            } catch (IOException e) {
+                throw new ClassNotFoundException(classFileName, e);
+            }
+        }
+
+        return defineClass(name, data, 0, data.length);
+    }
+
+    /**
+     * Notifies <code>ClassUnloader</code> about finalization.
+     */
+    protected void finalize() throws Throwable {
+
+        // notify ClassUnloader about finalization
+        if (classUnloader != null) {
+            classUnloader.finalized = true;
+        }
+
+        super.finalize();
+    }
+}