DataOutputEncoder.java

/*
 * 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.
 */

package org.apache.flink.api.java.typeutils.runtime;

import java.io.DataOutput;
import java.io.IOException;
import java.nio.ByteBuffer;

import org.apache.avro.io.Encoder;
import org.apache.avro.util.Utf8;
import org.apache.flink.annotation.Internal;

@Internal
public final class DataOutputEncoder extends Encoder implements java.io.Serializable {
	
	private static final long serialVersionUID = 1L;
	
	private transient DataOutput out;
	
	
	public void setOut(DataOutput out) {
		this.out = out;
	}


	@Override
	public void flush() throws IOException {}

	// --------------------------------------------------------------------------------------------
	// primitives
	// --------------------------------------------------------------------------------------------
	
	@Override
	public void writeNull() {}
	

	@Override
	public void writeBoolean(boolean b) throws IOException {
		out.writeBoolean(b);
	}

	@Override
	public void writeInt(int n) throws IOException {
		out.writeInt(n);
	}

	@Override
	public void writeLong(long n) throws IOException {
		out.writeLong(n);
	}

	@Override
	public void writeFloat(float f) throws IOException {
		out.writeFloat(f);
	}

	@Override
	public void writeDouble(double d) throws IOException {
		out.writeDouble(d);
	}
	
	@Override
	public void writeEnum(int e) throws IOException {
		out.writeInt(e);
	}
	
	
	// --------------------------------------------------------------------------------------------
	// bytes
	// --------------------------------------------------------------------------------------------

	@Override
	public void writeFixed(byte[] bytes, int start, int len) throws IOException {
		out.write(bytes, start, len);
	}
	
	@Override
	public void writeBytes(byte[] bytes, int start, int len) throws IOException {
		out.writeInt(len);
		if (len > 0) {
			out.write(bytes, start, len);
		}
	}
	
	@Override
	public void writeBytes(ByteBuffer bytes) throws IOException {
		int num = bytes.remaining();
		out.writeInt(num);
		
		if (num > 0) {
			writeFixed(bytes);
		}
	}
	
	// --------------------------------------------------------------------------------------------
	// strings
	// --------------------------------------------------------------------------------------------

	@Override
	public void writeString(String str) throws IOException {
		byte[] bytes = Utf8.getBytesFor(str);
		writeBytes(bytes, 0, bytes.length);
	}
	
	@Override
	public void writeString(Utf8 utf8) throws IOException {
		writeBytes(utf8.getBytes(), 0, utf8.getByteLength());
		
	}

	// --------------------------------------------------------------------------------------------
	// collection types
	// --------------------------------------------------------------------------------------------

	@Override
	public void writeArrayStart() {}

	@Override
	public void setItemCount(long itemCount) throws IOException {
		if (itemCount > 0) {
			writeVarLongCount(out, itemCount);
		}
	}

	@Override
	public void startItem() {}

	@Override
	public void writeArrayEnd() throws IOException {
		// write a single byte 0, shortcut for a var-length long of 0
		out.write(0);
	}

	@Override
	public void writeMapStart() {}

	@Override
	public void writeMapEnd() throws IOException {
		// write a single byte 0, shortcut for a var-length long of 0
		out.write(0);
	}

	// --------------------------------------------------------------------------------------------
	// union
	// --------------------------------------------------------------------------------------------
	
	@Override
	public void writeIndex(int unionIndex) throws IOException {
		out.writeInt(unionIndex);
	}
	
	// --------------------------------------------------------------------------------------------
	// utils
	// --------------------------------------------------------------------------------------------
		
	
	public static final void writeVarLongCount(DataOutput out, long val) throws IOException {
		if (val < 0) {
			throw new IOException("Illegal count (must be non-negative): " + val);
		}
		
		while ((val & ~0x7FL) != 0) {
			out.write(((int) val) | 0x80);
			val >>>= 7;
		}
		out.write((int) val);
	}
	
	private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
		// Read in size, and any hidden stuff
		s.defaultReadObject();

		this.out = null;
	}
}