+++ /dev/null
-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.util.HashMap;
-import java.util.Map;
-
-/**
- * Abstract base class for performing read operations of Lucene's low-level
- * data types.
- */
-public abstract class DataInput implements Cloneable {
-
- private boolean preUTF8Strings; // true if we are reading old (modified UTF8) string format
-
- /** Call this if readString should read characters stored
- * in the old modified UTF8 format (length in java chars
- * and java's modified UTF8 encoding). This is used for
- * indices written pre-2.4 See LUCENE-510 for details. */
- public void setModifiedUTF8StringsMode() {
- preUTF8Strings = true;
- }
-
- /** Reads and returns a single byte.
- * @see DataOutput#writeByte(byte)
- */
- public abstract byte readByte() throws IOException;
-
- /** Reads a specified number of bytes into an array at the specified offset.
- * @param b the array to read bytes into
- * @param offset the offset in the array to start storing bytes
- * @param len the number of bytes to read
- * @see DataOutput#writeBytes(byte[],int)
- */
- public abstract void readBytes(byte[] b, int offset, int len)
- throws IOException;
-
- /** Reads a specified number of bytes into an array at the
- * specified offset with control over whether the read
- * should be buffered (callers who have their own buffer
- * should pass in "false" for useBuffer). Currently only
- * {@link BufferedIndexInput} respects this parameter.
- * @param b the array to read bytes into
- * @param offset the offset in the array to start storing bytes
- * @param len the number of bytes to read
- * @param useBuffer set to false if the caller will handle
- * buffering.
- * @see DataOutput#writeBytes(byte[],int)
- */
- public void readBytes(byte[] b, int offset, int len, boolean useBuffer)
- throws IOException
- {
- // Default to ignoring useBuffer entirely
- readBytes(b, offset, len);
- }
-
- /** Reads two bytes and returns a short.
- * @see DataOutput#writeByte(byte)
- */
- public short readShort() throws IOException {
- return (short) (((readByte() & 0xFF) << 8) | (readByte() & 0xFF));
- }
-
- /** Reads four bytes and returns an int.
- * @see DataOutput#writeInt(int)
- */
- public int readInt() throws IOException {
- return ((readByte() & 0xFF) << 24) | ((readByte() & 0xFF) << 16)
- | ((readByte() & 0xFF) << 8) | (readByte() & 0xFF);
- }
-
- /** Reads an int stored in variable-length format. Reads between one and
- * five bytes. Smaller values take fewer bytes. Negative numbers are not
- * supported.
- * @see DataOutput#writeVInt(int)
- */
- public int readVInt() throws IOException {
- /* This is the original code of this method,
- * but a Hotspot bug (see LUCENE-2975) corrupts the for-loop if
- * readByte() is inlined. So the loop was unwinded!
- byte b = readByte();
- int i = b & 0x7F;
- for (int shift = 7; (b & 0x80) != 0; shift += 7) {
- b = readByte();
- i |= (b & 0x7F) << shift;
- }
- return i;
- */
- byte b = readByte();
- int i = b & 0x7F;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7F) << 7;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7F) << 14;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7F) << 21;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- assert (b & 0x80) == 0;
- return i | ((b & 0x7F) << 28);
- }
-
- /** Reads eight bytes and returns a long.
- * @see DataOutput#writeLong(long)
- */
- public long readLong() throws IOException {
- return (((long)readInt()) << 32) | (readInt() & 0xFFFFFFFFL);
- }
-
- /** Reads a long stored in variable-length format. Reads between one and
- * nine bytes. Smaller values take fewer bytes. Negative numbers are not
- * supported. */
- public long readVLong() throws IOException {
- /* This is the original code of this method,
- * but a Hotspot bug (see LUCENE-2975) corrupts the for-loop if
- * readByte() is inlined. So the loop was unwinded!
- byte b = readByte();
- long i = b & 0x7F;
- for (int shift = 7; (b & 0x80) != 0; shift += 7) {
- b = readByte();
- i |= (b & 0x7FL) << shift;
- }
- return i;
- */
- byte b = readByte();
- long i = b & 0x7FL;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 7;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 14;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 21;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 28;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 35;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 42;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- i |= (b & 0x7FL) << 49;
- if ((b & 0x80) == 0) return i;
- b = readByte();
- assert (b & 0x80) == 0;
- return i | ((b & 0x7FL) << 56);
- }
-
- /** Reads a string.
- * @see DataOutput#writeString(String)
- */
- public String readString() throws IOException {
- if (preUTF8Strings)
- return readModifiedUTF8String();
- int length = readVInt();
- final byte[] bytes = new byte[length];
- readBytes(bytes, 0, length);
- return new String(bytes, 0, length, "UTF-8");
- }
-
- private String readModifiedUTF8String() throws IOException {
- int length = readVInt();
- final char[] chars = new char[length];
- readChars(chars, 0, length);
- return new String(chars, 0, length);
- }
-
- /** Reads Lucene's old "modified UTF-8" encoded
- * characters into an array.
- * @param buffer the array to read characters into
- * @param start the offset in the array to start storing characters
- * @param length the number of characters to read
- * @see DataOutput#writeChars(String,int,int)
- * @deprecated -- please use readString or readBytes
- * instead, and construct the string
- * from those utf8 bytes
- */
- @Deprecated
- public void readChars(char[] buffer, int start, int length)
- throws IOException {
- final int end = start + length;
- for (int i = start; i < end; i++) {
- byte b = readByte();
- if ((b & 0x80) == 0)
- buffer[i] = (char)(b & 0x7F);
- else if ((b & 0xE0) != 0xE0) {
- buffer[i] = (char)(((b & 0x1F) << 6)
- | (readByte() & 0x3F));
- } else {
- buffer[i] = (char)(((b & 0x0F) << 12)
- | ((readByte() & 0x3F) << 6)
- | (readByte() & 0x3F));
- }
- }
- }
-
- /** Returns a clone of this stream.
- *
- * <p>Clones of a stream access the same data, and are positioned at the same
- * point as the stream they were cloned from.
- *
- * <p>Expert: Subclasses must ensure that clones may be positioned at
- * different points in the input from each other and from the stream they
- * were cloned from.
- */
- @Override
- public Object clone() {
- DataInput clone = null;
- try {
- clone = (DataInput)super.clone();
- } catch (CloneNotSupportedException e) {}
-
- return clone;
- }
-
- public Map<String,String> readStringStringMap() throws IOException {
- final Map<String,String> map = new HashMap<String,String>();
- final int count = readInt();
- for(int i=0;i<count;i++) {
- final String key = readString();
- final String val = readString();
- map.put(key, val);
- }
-
- return map;
- }
-}
fnp / pylucene.git / blobdiff