### Eclipse Workspace Patch 1.0
#P jackrabbit-core
Index: src/main/java/org/apache/jackrabbit/core/state/NodeState.java
===================================================================
--- src/main/java/org/apache/jackrabbit/core/state/NodeState.java	(revision 1685932)
+++ src/main/java/org/apache/jackrabbit/core/state/NodeState.java	(working copy)
@@ -110,13 +110,48 @@
         this.nodeTypeName = nodeTypeName;
     }
 
+static HashSet<String> traces = new HashSet<String>();
+void printTrace() {
+    StringBuilder buff = new StringBuilder();
+    for(StackTraceElement e : Thread.currentThread().getStackTrace()) {
+        String x = e.toString();
+        buff.append(x).append('\n');
+        if (x.indexOf("RandomChange") >= 0) {
+            if (x.indexOf("RandomChange.setUp") >= 0) {
+                return;
+            }
+            if (x.indexOf("RandomChange.init") >= 0) {
+                return;
+            }
+            break;
+        }
+    }
+    String s = buff.toString();
+    if(!traces.contains(s)) {
+        traces.add(s);
+        System.out.println(s);
+    }
+}
+
+private static void waitABit() {
+    try {
+        Thread.yield();
+        Thread.sleep(1);
+    } catch (InterruptedException e) {
+        // TODO Auto-generated catch block
+        e.printStackTrace();
+    }
+}
+    
     //-------------------------------------------------------< public methods >
     /**
      * {@inheritDoc}
      */
     @Override
     public synchronized void copy(ItemState state, boolean syncModCount) {
+waitABit();        
         synchronized (state) {
+//printTrace();            
             NodeState nodeState = (NodeState) state;
             id = nodeState.id;
             parentId = nodeState.parentId;
Index: src/test/java/org/apache/jackrabbit/core/deadlock/repository.xml
===================================================================
--- src/test/java/org/apache/jackrabbit/core/deadlock/repository.xml	(revision 0)
+++ src/test/java/org/apache/jackrabbit/core/deadlock/repository.xml	(working copy)
@@ -0,0 +1,153 @@
+<?xml version="1.0"?>
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You 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.
+-->
+
+<!DOCTYPE Repository
+          PUBLIC "-//The Apache Software Foundation//DTD Jackrabbit 2.0//EN"
+          "http://jackrabbit.apache.org/dtd/repository-2.0.dtd">
+
+<!-- Example Repository Configuration File
+     Used by
+     - org.apache.jackrabbit.core.config.RepositoryConfigTest.java
+     -
+-->
+<Repository>
+    <!--
+        virtual file system where the repository stores global state
+        (e.g. registered namespaces, custom node types, etc.)
+    -->
+    <FileSystem class="org.apache.jackrabbit.core.fs.local.LocalFileSystem">
+        <param name="path" value="${rep.home}/repository"/>
+    </FileSystem>
+
+    <!--
+        data store configuration
+    -->
+    <DataStore class="org.apache.jackrabbit.core.data.FileDataStore"/>
+
+    <!--
+        security configuration
+    -->
+    <Security appName="Jackrabbit">
+        <!--
+            security manager:
+            class: FQN of class implementing the JackrabbitSecurityManager interface
+        -->
+        <SecurityManager class="org.apache.jackrabbit.core.DefaultSecurityManager" workspaceName="security">
+            <!--
+            workspace access:
+            class: FQN of class implementing the WorkspaceAccessManager interface
+            -->
+            <!-- <WorkspaceAccessManager class="..."/> -->
+            <!-- <param name="config" value="${rep.home}/security.xml"/> -->
+        </SecurityManager>
+
+        <!--
+            access manager:
+            class: FQN of class implementing the AccessManager interface
+        -->
+        <AccessManager class="org.apache.jackrabbit.core.security.DefaultAccessManager">
+            <!-- <param name="config" value="${rep.home}/access.xml"/> -->
+        </AccessManager>
+
+        <LoginModule class="org.apache.jackrabbit.core.security.authentication.DefaultLoginModule">
+           <!-- 
+              anonymous user name ('anonymous' is the default value)
+            -->
+           <param name="anonymousId" value="anonymous"/>
+           <!--
+              administrator user id (default value if param is missing is 'admin')
+            -->
+           <param name="adminId" value="admin"/>
+        </LoginModule>
+    </Security>
+
+    <!--
+        location of workspaces root directory and name of default workspace
+    -->
+    <Workspaces rootPath="${rep.home}/workspaces" defaultWorkspace="default"/>
+    <!--
+        workspace configuration template:
+        used to create the initial workspace if there's no workspace yet
+    -->
+    <Workspace name="${wsp.name}">
+        <!--
+            virtual file system of the workspace:
+            class: FQN of class implementing the FileSystem interface
+        -->
+        <FileSystem class="org.apache.jackrabbit.core.fs.local.LocalFileSystem">
+            <param name="path" value="${wsp.home}"/>
+        </FileSystem>
+        <!--
+            persistence manager of the workspace:
+            class: FQN of class implementing the PersistenceManager interface
+        -->
+        <PersistenceManager class="org.apache.jackrabbit.core.persistence.pool.DerbyPersistenceManager">
+          <param name="url" value="jdbc:derby:${wsp.home}/db;create=true"/>
+          <param name="schemaObjectPrefix" value="${wsp.name}_"/>
+        </PersistenceManager>
+        <!--
+            Search index and the file system it uses.
+            class: FQN of class implementing the QueryHandler interface
+        <SearchIndex class="org.apache.jackrabbit.core.query.lucene.SearchIndex">
+            <param name="path" value="${wsp.home}/index"/>
+            <param name="supportHighlighting" value="true"/>
+        </SearchIndex>
+        -->
+    </Workspace>
+
+    <!--
+        Configures the versioning
+    -->
+    <Versioning rootPath="${rep.home}/version">
+        <!--
+            Configures the filesystem to use for versioning for the respective
+            persistence manager
+        -->
+        <FileSystem class="org.apache.jackrabbit.core.fs.local.LocalFileSystem">
+            <param name="path" value="${rep.home}/version" />
+        </FileSystem>
+
+        <!--
+            Configures the persistence manager to be used for persisting version state.
+            Please note that the current versioning implementation is based on
+            a 'normal' persistence manager, but this could change in future
+            implementations.
+        -->
+        <PersistenceManager class="org.apache.jackrabbit.core.persistence.pool.DerbyPersistenceManager">
+          <param name="url" value="jdbc:derby:${rep.home}/version/db;create=true"/>
+          <param name="schemaObjectPrefix" value="version_"/>
+        </PersistenceManager>
+    </Versioning>
+
+    <!--
+        Search index for content that is shared repository wide
+        (/jcr:system tree, contains mainly versions)
+    -->
+    <!--
+    <SearchIndex class="org.apache.jackrabbit.core.query.lucene.SearchIndex">
+        <param name="path" value="${rep.home}/repository/index"/>
+        <param name="supportHighlighting" value="true"/>
+    </SearchIndex>
+
+
+        Run with a cluster journal
+    <Cluster id="node1">
+        <Journal class="org.apache.jackrabbit.core.journal.MemoryJournal"/>
+    </Cluster>
+    -->
+</Repository>
Index: src/test/java/org/apache/jackrabbit/core/deadlock/RandomChange.java
===================================================================
--- src/test/java/org/apache/jackrabbit/core/deadlock/RandomChange.java	(revision 0)
+++ src/test/java/org/apache/jackrabbit/core/deadlock/RandomChange.java	(working copy)
@@ -0,0 +1,142 @@
+package org.apache.jackrabbit.core.deadlock;
+
+import java.util.Random;
+
+import javax.jcr.InvalidItemStateException;
+import javax.jcr.ItemNotFoundException;
+import javax.jcr.Node;
+import javax.jcr.RepositoryException;
+import javax.jcr.Session;
+
+import org.apache.jackrabbit.test.AbstractJCRTest;
+
+public class RandomChange extends AbstractJCRTest {
+    
+    static final String TEST_ROOT = "test" + System.currentTimeMillis() + "_";
+
+    private Session session;
+
+    public void setUp() throws Exception {
+        super.setUp();
+        session = testRootNode.getSession();
+    }
+
+//    public void testRandomized() throws Exception {
+//        for(int test = 0; test < 100; test++) {
+//            System.out.println("test " + test);
+//            init(s1);
+//            Random r = new Random(test);
+//            for(int i=0; i<100; i++) {
+//                Session s = r.nextBoolean() ? s1 : s2;
+//                randomOp(r, s);
+//            }
+//        }
+//    }
+    
+    public void testRandomizedConcurrent() throws Exception {
+        for(int i=0;; i++) {
+            System.out.println("i: " + i);
+            oneRandomizedConcurrent(i);
+        }
+    }
+    
+    private void oneRandomizedConcurrent(final int index) throws Exception {
+        int threadCount = 4;
+//        int threadCount = 10;
+        final boolean[] stop = new boolean[1];
+        final Exception[] ex = new Exception[1];
+        final Random r = new Random();
+        init(session, index);
+        Thread[] threads = new Thread[threadCount];
+        for(int i=0; i<threadCount; i++) {
+            threads[i] = new Thread() {
+                @Override
+                public void run() {
+                    try {
+                        Session s = getHelper().getReadWriteSession();
+                        while(!stop[0]) {
+                            randomOp(r, s, index);
+                        }
+                        s.logout();
+                    } catch (Exception e) {                
+    e.printStackTrace();                    
+                        ex[0] = e;
+                    }
+                }
+            };
+        }
+        for(int i=0; i<threadCount; i++) {
+            threads[i].start();
+        }
+        Thread.sleep(1000);
+        stop[0] = true;
+        for(int i=0; i<threadCount; i++) {
+            threads[i].join();
+        }
+        if (ex[0] != null) {
+            throw ex[0];
+        }
+    }
+    
+    private static void init(Session s, int index) throws Exception {
+        s.refresh(false);
+        Node root = s.getRootNode();
+        if (root.hasNode(TEST_ROOT + index)) {
+            root.getNode(TEST_ROOT + index).remove();
+            s.save();
+        }
+        root.addNode(TEST_ROOT + index);
+        s.save();
+    }
+    
+    static void randomOp(Random r, Session s, int index) throws Exception {
+        switch (r.nextInt(10)) {
+        case 0:
+            try {
+                s.save();
+            } catch (RepositoryException e) {
+                // ignore
+            } catch (NullPointerException e) {
+                // TODO what is this?
+            }
+            return;
+        case 1:
+//            s.refresh(true);
+//            return;
+//        case 2:
+//            s.refresh(false);
+//            return;
+        }
+        String nodeName = "n" + r.nextInt(4);
+        Node node = s.getRootNode().getNode(TEST_ROOT + index);
+        try {
+            if (nodeName.equals("n0") && r.nextBoolean()) {
+                node = node.getNode(nodeName);
+                nodeName = "n" + r.nextInt(4);
+            }
+            if (node.hasNode(nodeName)) {
+                Node n;
+                n = node.getNode(nodeName);
+                if (r.nextBoolean()) {
+                    n.remove();
+                } else {
+                    n.setProperty("x", r.nextInt(4));
+                }
+            } else {
+                node.addNode(nodeName);
+            }
+//            if (r.nextInt(10) == 0) {
+//                node.save();
+//            }
+        } catch (RepositoryException e) {
+            // ignore
+        } catch (NullPointerException e) {
+            // TODO what is this?
+        }
+    }
+
+    protected void tearDown() throws Exception {
+        super.tearDown();
+    }
+
+}
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