--- /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.Map;
+
+import org.apache.lucene.util.BytesRef;
+import org.apache.lucene.util.UnicodeUtil;
+
+/**
+ * Abstract base class for performing write operations of Lucene's low-level
+ * data types.
+ */
+public abstract class DataOutput {
+
+ /** Writes a single byte.
+ * @see IndexInput#readByte()
+ */
+ public abstract void writeByte(byte b) throws IOException;
+
+ /** Writes an array of bytes.
+ * @param b the bytes to write
+ * @param length the number of bytes to write
+ * @see DataInput#readBytes(byte[],int,int)
+ */
+ public void writeBytes(byte[] b, int length) throws IOException {
+ writeBytes(b, 0, length);
+ }
+
+ /** Writes an array of bytes.
+ * @param b the bytes to write
+ * @param offset the offset in the byte array
+ * @param length the number of bytes to write
+ * @see DataInput#readBytes(byte[],int,int)
+ */
+ public abstract void writeBytes(byte[] b, int offset, int length) throws IOException;
+
+ /** Writes an int as four bytes.
+ * @see DataInput#readInt()
+ */
+ public void writeInt(int i) throws IOException {
+ writeByte((byte)(i >> 24));
+ writeByte((byte)(i >> 16));
+ writeByte((byte)(i >> 8));
+ writeByte((byte) i);
+ }
+
+ /** Writes an int in a variable-length format. Writes between one and
+ * five bytes. Smaller values take fewer bytes. Negative numbers are not
+ * supported.
+ * @see DataInput#readVInt()
+ */
+ public final void writeVInt(int i) throws IOException {
+ while ((i & ~0x7F) != 0) {
+ writeByte((byte)((i & 0x7f) | 0x80));
+ i >>>= 7;
+ }
+ writeByte((byte)i);
+ }
+
+ /** Writes a long as eight bytes.
+ * @see DataInput#readLong()
+ */
+ public void writeLong(long i) throws IOException {
+ writeInt((int) (i >> 32));
+ writeInt((int) i);
+ }
+
+ /** Writes an long in a variable-length format. Writes between one and nine
+ * bytes. Smaller values take fewer bytes. Negative numbers are not
+ * supported.
+ * @see DataInput#readVLong()
+ */
+ public final void writeVLong(long i) throws IOException {
+ while ((i & ~0x7F) != 0) {
+ writeByte((byte)((i & 0x7f) | 0x80));
+ i >>>= 7;
+ }
+ writeByte((byte)i);
+ }
+
+ /** Writes a string.
+ * @see DataInput#readString()
+ */
+ public void writeString(String s) throws IOException {
+ final BytesRef utf8Result = new BytesRef(10);
+ UnicodeUtil.UTF16toUTF8(s, 0, s.length(), utf8Result);
+ writeVInt(utf8Result.length);
+ writeBytes(utf8Result.bytes, 0, utf8Result.length);
+ }
+
+ private static int COPY_BUFFER_SIZE = 16384;
+ private byte[] copyBuffer;
+
+ /** Copy numBytes bytes from input to ourself. */
+ public void copyBytes(DataInput input, long numBytes) throws IOException {
+ assert numBytes >= 0: "numBytes=" + numBytes;
+ long left = numBytes;
+ if (copyBuffer == null)
+ copyBuffer = new byte[COPY_BUFFER_SIZE];
+ while(left > 0) {
+ final int toCopy;
+ if (left > COPY_BUFFER_SIZE)
+ toCopy = COPY_BUFFER_SIZE;
+ else
+ toCopy = (int) left;
+ input.readBytes(copyBuffer, 0, toCopy);
+ writeBytes(copyBuffer, 0, toCopy);
+ left -= toCopy;
+ }
+ }
+
+ /** Writes a sub sequence of characters from s as the old
+ * format (modified UTF-8 encoded bytes).
+ * @param s the source of the characters
+ * @param start the first character in the sequence
+ * @param length the number of characters in the sequence
+ * @deprecated -- please pre-convert to utf8 bytes
+ * instead or use {@link #writeString}
+ */
+ @Deprecated
+ public void writeChars(String s, int start, int length)
+ throws IOException {
+ final int end = start + length;
+ for (int i = start; i < end; i++) {
+ final int code = s.charAt(i);
+ if (code >= 0x01 && code <= 0x7F)
+ writeByte((byte)code);
+ else if (((code >= 0x80) && (code <= 0x7FF)) || code == 0) {
+ writeByte((byte)(0xC0 | (code >> 6)));
+ writeByte((byte)(0x80 | (code & 0x3F)));
+ } else {
+ writeByte((byte)(0xE0 | (code >>> 12)));
+ writeByte((byte)(0x80 | ((code >> 6) & 0x3F)));
+ writeByte((byte)(0x80 | (code & 0x3F)));
+ }
+ }
+ }
+
+ /** Writes a sub sequence of characters from char[] as
+ * the old format (modified UTF-8 encoded bytes).
+ * @param s the source of the characters
+ * @param start the first character in the sequence
+ * @param length the number of characters in the sequence
+ * @deprecated -- please pre-convert to utf8 bytes instead or use {@link #writeString}
+ */
+ @Deprecated
+ public void writeChars(char[] s, int start, int length)
+ throws IOException {
+ final int end = start + length;
+ for (int i = start; i < end; i++) {
+ final int code = s[i];
+ if (code >= 0x01 && code <= 0x7F)
+ writeByte((byte)code);
+ else if (((code >= 0x80) && (code <= 0x7FF)) || code == 0) {
+ writeByte((byte)(0xC0 | (code >> 6)));
+ writeByte((byte)(0x80 | (code & 0x3F)));
+ } else {
+ writeByte((byte)(0xE0 | (code >>> 12)));
+ writeByte((byte)(0x80 | ((code >> 6) & 0x3F)));
+ writeByte((byte)(0x80 | (code & 0x3F)));
+ }
+ }
+ }
+
+ public void writeStringStringMap(Map<String,String> map) throws IOException {
+ if (map == null) {
+ writeInt(0);
+ } else {
+ writeInt(map.size());
+ for(final Map.Entry<String, String> entry: map.entrySet()) {
+ writeString(entry.getKey());
+ writeString(entry.getValue());
+ }
+ }
+ }
+}
fnp / pylucene.git / blobdiff