HBASE-2909 SoftValueSortedMap is broken, can generate NPEs

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@985383 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -475,6 +475,7 @@ Release 0.21.0 - Unreleased
    HBASE-2905  NPE when inserting mass data via REST interface (Sandy Yin via
                Andrew Purtell)
    HBASE-2908  Wrong order of null-check [in TIF] (Libor Dener via Stack)
+   HBASE-2909  SoftValueSortedMap is broken, can generate NPEs
 
   IMPROVEMENTS
    HBASE-1760  Cleanup TODOs in HTable

src/main/java/org/apache/hadoop/hbase/util/SoftValue.java

@@ -1,49 +0,0 @@
-/**
- * Copyright 2010 The Apache Software Foundation
- *
- * 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.
- */
-package org.apache.hadoop.hbase.util;
-
-import java.lang.ref.ReferenceQueue;
-import java.lang.ref.SoftReference;
-import java.util.Map;
-
-/**
- * A SoftReference derivative so that we can track down what keys to remove.
- */
-class SoftValue<K, V> extends SoftReference<V> implements Map.Entry<K, V> {
-  private final K key;
-
-  @SuppressWarnings("unchecked")
-  SoftValue(K key, V value, ReferenceQueue queue) {
-    super(value, queue);
-    this.key = key;
-  }
-
-  public K getKey() {
-    return this.key;
-  }
-
-  public V getValue() {
-    return get();
-  }
-
-  public V setValue(V value) {
-    throw new RuntimeException("Not implemented");
-  }
-}

src/main/java/org/apache/hadoop/hbase/util/SoftValueMap.java

@@ -1,146 +0,0 @@
-/**
- * Copyright 2010 The Apache Software Foundation
- *
- * 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.
- */
-package org.apache.hadoop.hbase.util;
-
-import java.lang.ref.ReferenceQueue;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
-
-/**
- * A Map that uses Soft Reference values internally. Use as a simple cache.
- *
- * @param <K> key class
- * @param <V> value class
- */
-public class SoftValueMap<K,V> implements Map<K,V> {
-  private final Map<K, SoftValue<K,V>> internalMap =
-    new HashMap<K, SoftValue<K,V>>();
-  private final ReferenceQueue<?> rq;
-
-  public SoftValueMap() {
-    this(new ReferenceQueue());
-  }
-
-  public SoftValueMap(final ReferenceQueue<?> rq) {
-    this.rq = rq;
-  }
-
-  /**
-   * Checks soft references and cleans any that have been placed on
-   * ReferenceQueue.
-   * @return How many references cleared.
-   */
-  @SuppressWarnings({"unchecked"})
-  public int checkReferences() {
-    int i = 0;
-    for (Object obj; (obj = this.rq.poll()) != null;) {
-      i++;
-      this.internalMap.remove(((SoftValue<K,V>)obj).getKey());
-    }
-    return i;
-  }
-
-  public V put(K key, V value) {
-    checkReferences();
-    SoftValue<K,V> oldValue = this.internalMap.put(key,
-      new SoftValue<K,V>(key, value, this.rq));
-    return oldValue == null ? null : oldValue.get();
-  }
-
-  @SuppressWarnings("unchecked")
-  public void putAll(Map map) {
-    throw new RuntimeException("Not implemented");
-  }
-
-  @SuppressWarnings({"SuspiciousMethodCalls"})
-  public V get(Object key) {
-    checkReferences();
-    SoftValue<K,V> value = this.internalMap.get(key);
-    if (value == null) {
-      return null;
-    }
-    if (value.get() == null) {
-      this.internalMap.remove(key);
-      return null;
-    }
-    return value.get();
-  }
-
-  public V remove(Object key) {
-    checkReferences();
-    SoftValue<K,V> value = this.internalMap.remove(key);
-    return value == null ? null : value.get();
-  }
-
-  public boolean containsKey(Object key) {
-    checkReferences();
-    return this.internalMap.containsKey(key);
-  }
-
-  public boolean containsValue(Object value) {
-/*    checkReferences();
-    return internalMap.containsValue(value);*/
-    throw new UnsupportedOperationException("Don't support containsValue!");
-  }
-
-  public boolean isEmpty() {
-    checkReferences();
-    return this.internalMap.isEmpty();
-  }
-
-  public int size() {
-    checkReferences();
-    return this.internalMap.size();
-  }
-
-  public void clear() {
-    checkReferences();
-    this.internalMap.clear();
-  }
-
-  public Set<K> keySet() {
-    checkReferences();
-    return this.internalMap.keySet();
-  }
-
-  public Set<Map.Entry<K,V>> entrySet() {
-    checkReferences();
-    Set<Map.Entry<K, SoftValue<K,V>>> entries = this.internalMap.entrySet();
-    Set<Map.Entry<K, V>> real_entries = new HashSet<Map.Entry<K,V>>();
-    for(Map.Entry<K, SoftValue<K,V>> entry : entries) {
-      real_entries.add(entry.getValue());
-    }
-    return real_entries;
-  }
-
-  public Collection<V> values() {
-    checkReferences();
-    Collection<SoftValue<K,V>> softValues = this.internalMap.values();
-    ArrayList<V> hardValues = new ArrayList<V>();
-    for(SoftValue<K,V> softValue : softValues) {
-      hardValues.add(softValue.get());
-    }
-    return hardValues;
-  }
-}

src/main/java/org/apache/hadoop/hbase/util/SoftValueSortedMap.java

@@ -20,6 +20,7 @@
 package org.apache.hadoop.hbase.util;
 
 import java.lang.ref.ReferenceQueue;
+import java.lang.ref.SoftReference;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Comparator;
@@ -72,7 +73,7 @@ public class SoftValueSortedMap<K,V> implements SortedMap<K,V> {
     for (Object obj; (obj = this.rq.poll()) != null;) {
       i++;
       //noinspection unchecked
-      this.internalMap.remove(((SoftValue<K,V>)obj).getKey());
+      this.internalMap.remove(((SoftValue<K,V>)obj).key);
     }
     return i;
   }
@@ -171,13 +172,7 @@ public class SoftValueSortedMap<K,V> implements SortedMap<K,V> {
   }
 
   public synchronized Set<Map.Entry<K,V>> entrySet() {
-    checkReferences();
+    throw new RuntimeException("Not implemented");
-    Set<Map.Entry<K, SoftValue<K,V>>> entries = this.internalMap.entrySet();
-    Set<Map.Entry<K, V>> real_entries = new TreeSet<Map.Entry<K,V>>();
-    for(Map.Entry<K, SoftValue<K,V>> entry : entries) {
-      real_entries.add(entry.getValue());
-    }
-    return real_entries;
   }
 
   public synchronized Collection<V> values() {
@@ -189,4 +184,13 @@ public class SoftValueSortedMap<K,V> implements SortedMap<K,V> {
     }
     return hardValues;
   }
+
+  private static class SoftValue<K,V> extends SoftReference<V> {
+    final K key;
+
+    SoftValue(K key, V value, ReferenceQueue q) {
+      super(value, q);
+      this.key = key;
+    }
+  }
 }