X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/RAMDirectory.java?ds=sidebyside

diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/RAMDirectory.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/RAMDirectory.java
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+package org.apache.lucene.store;
+
+/**
+ * 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.
+ */
+
+import java.io.IOException;
+import java.io.FileNotFoundException;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.apache.lucene.index.IndexFileNameFilter;
+import org.apache.lucene.util.ThreadInterruptedException;
+
+/**
+ * A memory-resident {@link Directory} implementation.  Locking
+ * implementation is by default the {@link SingleInstanceLockFactory}
+ * but can be changed with {@link #setLockFactory}.
+ */
+public class RAMDirectory extends Directory implements Serializable {
+
+  private static final long serialVersionUID = 1l;
+
+  protected final Map<String,RAMFile> fileMap = new ConcurrentHashMap<String,RAMFile>();
+  protected final AtomicLong sizeInBytes = new AtomicLong();
+  
+  // *****
+  // Lock acquisition sequence:  RAMDirectory, then RAMFile
+  // *****
+
+  /** Constructs an empty {@link Directory}. */
+  public RAMDirectory() {
+    try {
+      setLockFactory(new SingleInstanceLockFactory());
+    } catch (IOException e) {
+      // Cannot happen
+    }
+  }
+
+  /**
+   * Creates a new <code>RAMDirectory</code> instance from a different
+   * <code>Directory</code> implementation.  This can be used to load
+   * a disk-based index into memory.
+   * <P>
+   * This should be used only with indices that can fit into memory.
+   * <P>
+   * Note that the resulting <code>RAMDirectory</code> instance is fully
+   * independent from the original <code>Directory</code> (it is a
+   * complete copy).  Any subsequent changes to the
+   * original <code>Directory</code> will not be visible in the
+   * <code>RAMDirectory</code> instance.
+   *
+   * @param dir a <code>Directory</code> value
+   * @exception IOException if an error occurs
+   */
+  public RAMDirectory(Directory dir) throws IOException {
+    this(dir, false);
+  }
+  
+  private RAMDirectory(Directory dir, boolean closeDir) throws IOException {
+    this();
+
+    IndexFileNameFilter filter = IndexFileNameFilter.getFilter();
+    for (String file : dir.listAll()) {
+      if (filter.accept(null, file)) {
+        dir.copy(this, file, file);
+      }
+    }
+    if (closeDir) {
+      dir.close();
+    }
+  }
+
+  @Override
+  public final String[] listAll() {
+    ensureOpen();
+    // NOTE: fileMap.keySet().toArray(new String[0]) is broken in non Sun JDKs,
+    // and the code below is resilient to map changes during the array population.
+    Set<String> fileNames = fileMap.keySet();
+    List<String> names = new ArrayList<String>(fileNames.size());
+    for (String name : fileNames) names.add(name);
+    return names.toArray(new String[names.size()]);
+  }
+
+  /** Returns true iff the named file exists in this directory. */
+  @Override
+  public final boolean fileExists(String name) {
+    ensureOpen();
+    return fileMap.containsKey(name);
+  }
+
+  /** Returns the time the named file was last modified.
+   * @throws IOException if the file does not exist
+   */
+  @Override
+  public final long fileModified(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = fileMap.get(name);
+    if (file == null) {
+      throw new FileNotFoundException(name);
+    }
+    return file.getLastModified();
+  }
+
+  /** Set the modified time of an existing file to now.
+   * @throws IOException if the file does not exist
+   *  @deprecated Lucene never uses this API; it will be
+   *  removed in 4.0. */
+  @Override
+  @Deprecated
+  public void touchFile(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = fileMap.get(name);
+    if (file == null) {
+      throw new FileNotFoundException(name);
+    }
+    
+    long ts2, ts1 = System.currentTimeMillis();
+    do {
+      try {
+        Thread.sleep(0, 1);
+      } catch (InterruptedException ie) {
+        throw new ThreadInterruptedException(ie);
+      }
+      ts2 = System.currentTimeMillis();
+    } while(ts1 == ts2);
+    
+    file.setLastModified(ts2);
+  }
+
+  /** Returns the length in bytes of a file in the directory.
+   * @throws IOException if the file does not exist
+   */
+  @Override
+  public final long fileLength(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = fileMap.get(name);
+    if (file == null) {
+      throw new FileNotFoundException(name);
+    }
+    return file.getLength();
+  }
+  
+  /**
+   * Return total size in bytes of all files in this directory. This is
+   * currently quantized to RAMOutputStream.BUFFER_SIZE.
+   */
+  public final long sizeInBytes() {
+    ensureOpen();
+    return sizeInBytes.get();
+  }
+  
+  /** Removes an existing file in the directory.
+   * @throws IOException if the file does not exist
+   */
+  @Override
+  public void deleteFile(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = fileMap.remove(name);
+    if (file != null) {
+      file.directory = null;
+      sizeInBytes.addAndGet(-file.sizeInBytes);
+    } else {
+      throw new FileNotFoundException(name);
+    }
+  }
+
+  /** Creates a new, empty file in the directory with the given name. Returns a stream writing this file. */
+  @Override
+  public IndexOutput createOutput(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = newRAMFile();
+    RAMFile existing = fileMap.remove(name);
+    if (existing != null) {
+      sizeInBytes.addAndGet(-existing.sizeInBytes);
+      existing.directory = null;
+    }
+    fileMap.put(name, file);
+    return new RAMOutputStream(file);
+  }
+
+  /**
+   * Returns a new {@link RAMFile} for storing data. This method can be
+   * overridden to return different {@link RAMFile} impls, that e.g. override
+   * {@link RAMFile#newBuffer(int)}.
+   */
+  protected RAMFile newRAMFile() {
+    return new RAMFile(this);
+  }
+
+  /** Returns a stream reading an existing file. */
+  @Override
+  public IndexInput openInput(String name) throws IOException {
+    ensureOpen();
+    RAMFile file = fileMap.get(name);
+    if (file == null) {
+      throw new FileNotFoundException(name);
+    }
+    return new RAMInputStream(name, file);
+  }
+
+  /** Closes the store to future operations, releasing associated memory. */
+  @Override
+  public void close() {
+    isOpen = false;
+    fileMap.clear();
+  }
+}