/*
* Copyright 1999-2012 Alibaba Group.
*
* 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.alibaba.cobar.net.mysql;
import java.io.UnsupportedEncodingException;
import com.alibaba.cobar.mysql.BindValue;
import com.alibaba.cobar.mysql.BindValueUtil;
import com.alibaba.cobar.mysql.MySQLMessage;
import com.alibaba.cobar.mysql.PreparedStatement;
/**
* <pre>
* Bytes Name
* ----- ----
* 1 code
* 4 statement_id
* 1 flags
* 4 iteration_count
* (param_count+7)/8 null_bit_map
* 1 new_parameter_bound_flag (if new_params_bound == 1:)
* n*2 type of parameters
* n values for the parameters
* --------------------------------------------------------------------------------
* code: always COM_EXECUTE
*
* statement_id: statement identifier
*
* flags: reserved for future use. In MySQL 4.0, always 0.
* In MySQL 5.0:
* 0: CURSOR_TYPE_NO_CURSOR
* 1: CURSOR_TYPE_READ_ONLY
* 2: CURSOR_TYPE_FOR_UPDATE
* 4: CURSOR_TYPE_SCROLLABLE
*
* iteration_count: reserved for future use. Currently always 1.
*
* null_bit_map: A bitmap indicating parameters that are NULL.
* Bits are counted from LSB, using as many bytes
* as necessary ((param_count+7)/8)
* i.e. if the first parameter (parameter 0) is NULL, then
* the least significant bit in the first byte will be 1.
*
* new_parameter_bound_flag: Contains 1 if this is the first time
* that "execute" has been called, or if
* the parameters have been rebound.
*
* type: Occurs once for each parameter;
* The highest significant bit of this 16-bit value
* encodes the unsigned property. The other 15 bits
* are reserved for the type (only 8 currently used).
* This block is sent when parameters have been rebound
* or when a prepared statement is executed for the
* first time.
*
* values: for all non-NULL values, each parameters appends its value
* as described in Row Data Packet: Binary (column values)
* @see http://dev.mysql.com/doc/internals/en/execute-packet.html
* </pre>
*
* @author xianmao.hexm 2012-8-28
*/
public class ExecutePacket extends MySQLPacket {
public byte code;
public long statementId;
public byte flags;
public long iterationCount;
public byte[] nullBitMap;
public byte newParameterBoundFlag;
public BindValue[] values;
protected PreparedStatement pstmt;
public ExecutePacket(PreparedStatement pstmt) {
this.pstmt = pstmt;
this.values = new BindValue[pstmt.getParametersNumber()];
}
public void read(byte[] data, String charset) throws UnsupportedEncodingException {
MySQLMessage mm = new MySQLMessage(data);
packetLength = mm.readUB3();
packetId = mm.read();
code = mm.read();
statementId = mm.readUB4();
flags = mm.read();
iterationCount = mm.readUB4();
// 读取NULL指示器数据
int parameterCount = values.length;
nullBitMap = new byte[(parameterCount + 7) / 8];
for (int i = 0; i < nullBitMap.length; i++) {
nullBitMap[i] = mm.read();
}
// 当newParameterBoundFlag==1时，更新参数类型。
newParameterBoundFlag = mm.read();
if (newParameterBoundFlag == (byte) 1) {
for (int i = 0; i < parameterCount; i++) {
pstmt.getParametersType()[i] = mm.readUB2();
}
}
// 设置参数类型和读取参数值
byte[] nullBitMap = this.nullBitMap;
for (int i = 0; i < parameterCount; i++) {
BindValue bv = new BindValue();
bv.type = pstmt.getParametersType()[i];
if ((nullBitMap[i / 8] & (1 << (i & 7))) != 0) {
bv.isNull = true;
} else {
BindValueUtil.read(mm, bv, charset);
}
values[i] = bv;
}
}
@Override
public int calcPacketSize() {
// TODO Auto-generated method stub
return 0;
}
@Override
protected String getPacketInfo() {
return "MySQL Execute Packet";
}
}