pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / src / java / org / apache / lucene / index / ByteSliceWriter.java

diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/index/ByteSliceWriter.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/index/ByteSliceWriter.java
new file mode 100644 (file)
index 0000000..8103cb8
--- /dev/null
+++ b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/index/ByteSliceWriter.java
@@ -0,0 +1,89 @@
+package org.apache.lucene.index;
+
+/**
+ * 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.
+ */
+
+
+/**
+ * Class to write byte streams into slices of shared
+ * byte[].  This is used by DocumentsWriter to hold the
+ * posting list for many terms in RAM.
+ */
+
+final class ByteSliceWriter {
+
+  private byte[] slice;
+  private int upto;
+  private final ByteBlockPool pool;
+
+  int offset0;
+
+  public ByteSliceWriter(ByteBlockPool pool) {
+    this.pool = pool;
+  }
+
+  /**
+   * Set up the writer to write at address.
+   */ 
+  public void init(int address) {
+    slice = pool.buffers[address >> DocumentsWriter.BYTE_BLOCK_SHIFT];
+    assert slice != null;
+    upto = address & DocumentsWriter.BYTE_BLOCK_MASK;
+    offset0 = address;
+    assert upto < slice.length;
+  }
+
+  /** Write byte into byte slice stream */
+  public void writeByte(byte b) {
+    assert slice != null;
+    if (slice[upto] != 0) {
+      upto = pool.allocSlice(slice, upto);
+      slice = pool.buffer;
+      offset0 = pool.byteOffset;
+      assert slice != null;
+    }
+    slice[upto++] = b;
+    assert upto != slice.length;
+  }
+
+  public void writeBytes(final byte[] b, int offset, final int len) {
+    final int offsetEnd = offset + len;
+    while(offset < offsetEnd) {
+      if (slice[upto] != 0) {
+        // End marker
+        upto = pool.allocSlice(slice, upto);
+        slice = pool.buffer;
+        offset0 = pool.byteOffset;
+      }
+
+      slice[upto++] = b[offset++];
+      assert upto != slice.length;
+    }
+  }
+
+  public int getAddress() {
+    return upto + (offset0 & DocumentsWriter.BYTE_BLOCK_NOT_MASK);
+  }
+
+  public void writeVInt(int i) {
+    while ((i & ~0x7F) != 0) {
+      writeByte((byte)((i & 0x7f) | 0x80));
+      i >>>= 7;
+    }
+    writeByte((byte) i);
+  }
+}