com.github.pgasync.impl.io.CommandCompleteDecoder Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of postgres-async-driver Show documentation
Asynchronous PostgreSQL Java driver
The newest version!
/*
 * Licensed 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 com.github.pgasync.impl.io;

import com.github.pgasync.impl.message.CommandComplete;

import java.nio.ByteBuffer;

import static com.github.pgasync.impl.io.IO.getCString;

/**
 * See PostgreSQL message formats
 *
 *  * CommandComplete (B)
 *  Byte1('C')
 *      Identifies the message as a command-completed response.
 *  Int32
 *      Length of message contents in bytes, including self.
 *  String
 *      The command tag. This is usually a single word that identifies which SQL command was completed.
 *      For an INSERT command, the tag is INSERT oid rows, where rows is the number of rows inserted. oid is the object ID of the inserted row if rows is 1 and the target table has OIDs; otherwise oid is 0.
 *      For a DELETE command, the tag is DELETE rows where rows is the number of rows deleted.
 *      For an UPDATE command, the tag is UPDATE rows where rows is the number of rows updated.
 *      For a SELECT or CREATE TABLE AS command, the tag is SELECT rows where rows is the number of rows retrieved.
 *      For a MOVE command, the tag is MOVE rows where rows is the number of rows the cursor's position has been changed by.
 *      For a FETCH command, the tag is FETCH rows where rows is the number of rows that have been retrieved from the cursor.
 *      For a COPY command, the tag is COPY rows where rows is the number of rows copied. (Note: the row count appears only in PostgreSQL 8.2 and later.)
 * 
 *
 * @author Antti Laisi
 */
public class CommandCompleteDecoder implements Decoder {

    @Override
    public byte getMessageId() {
        return 'C';
    }

    @Override
    public CommandComplete read(ByteBuffer buffer) {
        byte[] tmp = new byte[255];
        String tag = getCString(buffer, tmp);
        return new CommandComplete(tag);
    }

}