Issue 180: when deserializing objects, the context class loader is used instead…

Issue 180: when deserializing objects, the context class loader is used instead of the default class loader if the system property "h2.useThreadContextClassLoader" is set. Thanks a lot to Noah Fontes for the patch!

h2/src/docsrc/html/changelog.html

@@ -19,7 +19,12 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>The optimization for "group by" was not working correctly if the group by column
+<ul><li>Issue 180: when deserializing objects, the context class loader is used 
+    instead of the default class loader if the system property "h2.useThreadContextClassLoader" is set.
+    Thanks a lot to Noah Fontes for the patch!
+</li><li>When using the exclusive mode, LOB operations could cause the thread to freeze.
+    This also affected the CreateCluster tool (when using BLOB or CLOB data).
+</li><li>The optimization for "group by" was not working correctly if the group by column
     was aliased in the select list.
 </li><li>Issue 326: improved support for case sensitive (mixed case) identifiers 
     without quotes when using DATABASE_TO_UPPER=FALSE.

h2/src/main/org/h2/constant/SysProperties.java

@@ -377,6 +377,13 @@ public class SysProperties {
      */
     public static final String URL_MAP = Utils.getProperty("h2.urlMap", null);
 
+    /**
+     * System property <code>h2.useThreadContextClassLoader</code> (default: false).<br />
+     * Instead of using the default class loader when deserializing objects,
+     * the current thread-context class loader will be used.
+     */
+    public static final boolean USE_THREAD_CONTEXT_CLASS_LOADER = Utils.getProperty("h2.useThreadContextClassLoader", false);
+
     /**
      * System property <code>h2.webMaxValueLength</code> (default: 100000).<br />
      * The H2 Console will abbreviate (truncate) result values larger than this size.

h2/src/main/org/h2/util/Utils.java

@@ -12,6 +12,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
+import java.io.ObjectStreamClass;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
@@ -250,7 +251,21 @@ public class Utils {
     public static Object deserialize(byte[] data) {
         try {
             ByteArrayInputStream in = new ByteArrayInputStream(data);
-            ObjectInputStream is = new ObjectInputStream(in);
+            ObjectInputStream is;
+            if (SysProperties.USE_THREAD_CONTEXT_CLASS_LOADER) {
+                final ClassLoader loader = Thread.currentThread().getContextClassLoader();
+                is = new ObjectInputStream(in) {
+                    protected Class<?> resolveClass(ObjectStreamClass desc) throws IOException, ClassNotFoundException {
+                        try {
+                            return Class.forName(desc.getName(), true, loader);
+                        } catch (ClassNotFoundException e) {
+                            return super.resolveClass(desc);
+                        }
+                    }
+                };
+            } else {
+                is = new ObjectInputStream(in);
+            }
             return is.readObject();
         } catch (Throwable e) {
             throw DbException.get(ErrorCode.DESERIALIZATION_FAILED_1, e, e.toString());

h2/src/test/org/h2/test/TestAll.java

@@ -137,6 +137,7 @@ import org.h2.test.unit.TestFtp;
 import org.h2.test.unit.TestIntArray;
 import org.h2.test.unit.TestIntIntHashMap;
 import org.h2.test.unit.TestJmx;
+import org.h2.test.unit.TestObjectDeserialization;
 import org.h2.test.unit.TestTraceSystem;
 import org.h2.test.unit.TestMathUtils;
 import org.h2.test.unit.TestNetUtils;
@@ -338,6 +339,7 @@ java org.h2.test.TestAll timer
         System.setProperty("h2.check2", "true");
         System.setProperty("h2.delayWrongPasswordMin", "0");
         System.setProperty("h2.delayWrongPasswordMax", "0");
+        System.setProperty("h2.useThreadContextClassLoader", "true");
 
         // System.setProperty("h2.storeLocalTime", "true");
 
@@ -668,6 +670,7 @@ kill -9 `jps -l | grep "org.h2.test." | cut -d " " -f 1`
         new TestMathUtils().runTest(this);
         new TestOldVersion().runTest(this);
         new TestNetUtils().runTest(this);
+        new TestObjectDeserialization().runTest(this);
         new TestMultiThreadedKernel().runTest(this);
         new TestOverflow().runTest(this);
         new TestPageStore().runTest(this);

h2/src/test/org/h2/test/unit/TestObjectDeserialization.java

+/*
+ * Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: Noah Fontes <nfontes@invectorate.com>
+ */
+package org.h2.test.unit;
+
+import org.h2.message.DbException;
+import org.h2.test.TestBase;
+import org.h2.util.StringUtils;
+import org.h2.util.Utils;
+
+/**
+ * Tests the ability to deserialize objects that are not part of the system class-
+ * loading scope.
+ */
+public class TestObjectDeserialization extends TestBase {
+
+    private static final String CLAZZ = "org.h2.test.unit.SampleObject";
+    private static final String OBJECT = "aced00057372001d6f72672e68322e746573742e756e69742e53616d706c654f626a65637400000000000000010200007870";
+
+    protected boolean usesThreadContextClassLoader;
+
+    /**
+     * Run just this test.
+     *
+     * @param a ignored
+     */
+    public static void main(String... a) throws Exception {
+        System.setProperty("h2.useThreadContextClassLoader", "true");
+        TestBase.createCaller().init().test();
+    }
+
+    public void test() throws Exception {
+        testThreadContextClassLoader();
+    }
+
+    private void testThreadContextClassLoader() throws Exception {
+        Thread.currentThread().setContextClassLoader(new TestClassLoader());
+        try {
+            Utils.deserialize(StringUtils.convertHexToBytes(OBJECT));
+            fail();
+        } catch (DbException e) {
+            // expected
+        }
+        assertTrue(usesThreadContextClassLoader);
+    }
+
+    /**
+     * A special class loader.
+     */
+    private class TestClassLoader extends ClassLoader {
+
+        public TestClassLoader() {
+            super();
+        }
+
+        protected synchronized Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
+            if (name.equals(CLAZZ)) {
+                usesThreadContextClassLoader = true;
+            }
+            return super.loadClass(name, resolve);
+        }
+
+    }
+
+}