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/ByteArrayDataInput.java diff --git a/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/ByteArrayDataInput.java b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/ByteArrayDataInput.java new file mode 100644 index 0000000..59dbb81 --- /dev/null +++ b/lucene-java-3.5.0/lucene/src/java/org/apache/lucene/store/ByteArrayDataInput.java @@ -0,0 +1,132 @@ +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 org.apache.lucene.util.BytesRef; + +/** @lucene.experimental */ +public final class ByteArrayDataInput extends DataInput { + + private byte[] bytes; + + private int pos; + private int limit; + + public ByteArrayDataInput(byte[] bytes) { + reset(bytes); + } + + public ByteArrayDataInput(byte[] bytes, int offset, int len) { + reset(bytes, offset, len); + } + + public ByteArrayDataInput() { + reset(BytesRef.EMPTY_BYTES); + } + + public void reset(byte[] bytes) { + reset(bytes, 0, bytes.length); + } + + public int getPosition() { + return pos; + } + + public void reset(byte[] bytes, int offset, int len) { + this.bytes = bytes; + pos = offset; + limit = offset + len; + } + + public boolean eof() { + return pos == limit; + } + + public void skipBytes(int count) { + pos += count; + assert pos <= limit; + } + + @Override + public short readShort() { + return (short) (((bytes[pos++] & 0xFF) << 8) | (bytes[pos++] & 0xFF)); + } + + @Override + public int readInt() { + assert pos+4 <= limit; + return ((bytes[pos++] & 0xFF) << 24) | ((bytes[pos++] & 0xFF) << 16) + | ((bytes[pos++] & 0xFF) << 8) | (bytes[pos++] & 0xFF); + } + + @Override + public long readLong() { + assert pos+8 <= limit; + final int i1 = ((bytes[pos++] & 0xff) << 24) | ((bytes[pos++] & 0xff) << 16) | + ((bytes[pos++] & 0xff) << 8) | (bytes[pos++] & 0xff); + final int i2 = ((bytes[pos++] & 0xff) << 24) | ((bytes[pos++] & 0xff) << 16) | + ((bytes[pos++] & 0xff) << 8) | (bytes[pos++] & 0xff); + return (((long)i1) << 32) | (i2 & 0xFFFFFFFFL); + } + + @Override + public int readVInt() { + checkBounds(); + byte b = bytes[pos++]; + int i = b & 0x7F; + for (int shift = 7; (b & 0x80) != 0; shift += 7) { + checkBounds(); + b = bytes[pos++]; + i |= (b & 0x7F) << shift; + } + return i; + } + + @Override + public long readVLong() { + checkBounds(); + byte b = bytes[pos++]; + long i = b & 0x7F; + for (int shift = 7; (b & 0x80) != 0; shift += 7) { + checkBounds(); + b = bytes[pos++]; + i |= (b & 0x7FL) << shift; + } + return i; + } + + // NOTE: AIOOBE not EOF if you read too much + @Override + public byte readByte() { + checkBounds(); + return bytes[pos++]; + } + + // NOTE: AIOOBE not EOF if you read too much + @Override + public void readBytes(byte[] b, int offset, int len) { + assert pos + len <= limit; + System.arraycopy(bytes, pos, b, offset, len); + pos += len; + } + + private boolean checkBounds() { + assert pos < limit; + return true; + } +}