实例说明ModBus的使用方法：

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主要用于JAVA 对ModBus以及串口的通讯操作

1，Test类用于接收数采仪数据，然后核对其CRC校验是否正确，不正确便丢弃，不作任何操作，正确就查找其设备号对应哪个站点，以及其检测指标。然后到DB中查找实时检测值，若未有实时数据可用本实例中的随机数代替，然后保存发送数据到数据库中。得到值后通过CRC16得到其校验码组成其要发送的字节，发送完毕。

2，主要涉及到的类有3个

DB.java 用户得到实时数据，保存发送数据到数据库中

Test.java 用户接收数采仪值，通过com串口发送到数采仪

ModBus的CRC16校验法

数采仪是参照国际HJ/T212-2005

CRC.javal类代码如下：

public class CRC16 {

static final String HEXES = "0123456789ABCDEF";

byte uchCRCHi = (byte) 0xFF;

byte uchCRCLo = (byte) 0xFF;

private static byte[] auchCRCHi = { 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x01,

(byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01,

(byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80,

(byte) 0x41, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01,

(byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80,

(byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x01,

(byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x01, (byte) 0xC0, (byte) 0x80,

(byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x00, (byte) 0xC1,

(byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80,

(byte) 0x41, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x00, (byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40, (byte) 0x01, (byte) 0xC0,

(byte) 0x80, (byte) 0x41, (byte) 0x00, (byte) 0xC1, (byte) 0x81,

(byte) 0x40, (byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41,

(byte) 0x01, (byte) 0xC0, (byte) 0x80, (byte) 0x41, (byte) 0x00,

(byte) 0xC1, (byte) 0x81, (byte) 0x40 };

private static byte[] auchCRCLo = { (byte) 0x00, (byte) 0xC0, (byte) 0xC1,

(byte) 0x01, (byte) 0xC3, (byte) 0x03, (byte) 0x02, (byte) 0xC2,

(byte) 0xC6, (byte) 0x06, (byte) 0x07, (byte) 0xC7, (byte) 0x05,

(byte) 0xC5, (byte) 0xC4, (byte) 0x04, (byte) 0xCC, (byte) 0x0C,

(byte) 0x0D, (byte) 0xCD, (byte) 0x0F, (byte) 0xCF, (byte) 0xCE,

(byte) 0x0E, (byte) 0x0A, (byte) 0xCA, (byte) 0xCB, (byte) 0x0B,

(byte) 0xC9, (byte) 0x09, (byte) 0x08, (byte) 0xC8, (byte) 0xD8,

(byte) 0x18, (byte) 0x19, (byte) 0xD9, (byte) 0x1B, (byte) 0xDB,

(byte) 0xDA, (byte) 0x1A, (byte) 0x1E, (byte) 0xDE, (byte) 0xDF,

(byte) 0x1F, (byte) 0xDD, (byte) 0x1D, (byte) 0x1C, (byte) 0xDC,

(byte) 0x14, (byte) 0xD4, (byte) 0xD5, (byte) 0x15, (byte) 0xD7,

(byte) 0x17, (byte) 0x16, (byte) 0xD6, (byte) 0xD2, (byte) 0x12,

(byte) 0x13, (byte) 0xD3, (byte) 0x11, (byte) 0xD1, (byte) 0xD0,

(byte) 0x10, (byte) 0xF0, (byte) 0x30, (byte) 0x31, (byte) 0xF1,

(byte) 0x33, (byte) 0xF3, (byte) 0xF2, (byte) 0x32, (byte) 0x36,

(byte) 0xF6, (byte) 0xF7, (byte) 0x37, (byte) 0xF5, (byte) 0x35,

(byte) 0x34, (byte) 0xF4, (byte) 0x3C, (byte) 0xFC, (byte) 0xFD,

(byte) 0x3D, (byte) 0xFF, (byte) 0x3F, (byte) 0x3E, (byte) 0xFE,

(byte) 0xFA, (byte) 0x3A, (byte) 0x3B, (byte) 0xFB, (byte) 0x39,

(byte) 0xF9, (byte) 0xF8, (byte) 0x38, (byte) 0x28, (byte) 0xE8,

(byte) 0xE9, (byte) 0x29, (byte) 0xEB, (byte) 0x2B, (byte) 0x2A,

(byte) 0xEA, (byte) 0xEE, (byte) 0x2E, (byte) 0x2F, (byte) 0xEF,

(byte) 0x2D, (byte) 0xED, (byte) 0xEC, (byte) 0x2C, (byte) 0xE4,

(byte) 0x24, (byte) 0x25, (byte) 0xE5, (byte) 0x27, (byte) 0xE7,

(byte) 0xE6, (byte) 0x26, (byte) 0x22, (byte) 0xE2, (byte) 0xE3,

(byte) 0x23, (byte) 0xE1, (byte) 0x21, (byte) 0x20, (byte) 0xE0,

(byte) 0xA0, (byte) 0x60, (byte) 0x61, (byte) 0xA1, (byte) 0x63,

(byte) 0xA3, (byte) 0xA2, (byte) 0x62, (byte) 0x66, (byte) 0xA6,

(byte) 0xA7, (byte) 0x67, (byte) 0xA5, (byte) 0x65, (byte) 0x64,

(byte) 0xA4, (byte) 0x6C, (byte) 0xAC, (byte) 0xAD, (byte) 0x6D,

(byte) 0xAF, (byte) 0x6F, (byte) 0x6E, (byte) 0xAE, (byte) 0xAA,

(byte) 0x6A, (byte) 0x6B, (byte) 0xAB, (byte) 0x69, (byte) 0xA9,

(byte) 0xA8, (byte) 0x68, (byte) 0x78, (byte) 0xB8, (byte) 0xB9,

(byte) 0x79, (byte) 0xBB, (byte) 0x7B, (byte) 0x7A, (byte) 0xBA,

(byte) 0xBE, (byte) 0x7E, (byte) 0x7F, (byte) 0xBF, (byte) 0x7D,

(byte) 0xBD, (byte) 0xBC, (byte) 0x7C, (byte) 0xB4, (byte) 0x74,

(byte) 0x75, (byte) 0xB5, (byte) 0x77, (byte) 0xB7, (byte) 0xB6,

(byte) 0x76, (byte) 0x72, (byte) 0xB2, (byte) 0xB3, (byte) 0x73,

(byte) 0xB1, (byte) 0x71, (byte) 0x70, (byte) 0xB0, (byte) 0x50,

(byte) 0x90, (byte) 0x91, (byte) 0x51, (byte) 0x93, (byte) 0x53,

(byte) 0x52, (byte) 0x92, (byte) 0x96, (byte) 0x56, (byte) 0x57,

(byte) 0x97, (byte) 0x55, (byte) 0x95, (byte) 0x94, (byte) 0x54,

(byte) 0x9C, (byte) 0x5C, (byte) 0x5D, (byte) 0x9D, (byte) 0x5F,

(byte) 0x9F, (byte) 0x9E, (byte) 0x5E, (byte) 0x5A, (byte) 0x9A,

(byte) 0x9B, (byte) 0x5B, (byte) 0x99, (byte) 0x59, (byte) 0x58,

(byte) 0x98, (byte) 0x88, (byte) 0x48, (byte) 0x49, (byte) 0x89,

(byte) 0x4B, (byte) 0x8B, (byte) 0x8A, (byte) 0x4A, (byte) 0x4E,

(byte) 0x8E, (byte) 0x8F, (byte) 0x4F, (byte) 0x8D, (byte) 0x4D,

(byte) 0x4C, (byte) 0x8C, (byte) 0x44, (byte) 0x84, (byte) 0x85,

(byte) 0x45, (byte) 0x87, (byte) 0x47, (byte) 0x46, (byte) 0x86,

(byte) 0x82, (byte) 0x42, (byte) 0x43, (byte) 0x83, (byte) 0x41,

(byte) 0x81, (byte) 0x80, (byte) 0x40 };

public int value;

public CRC16() {

value = 0;

}

public void update(byte[] puchMsg, int usDataLen) {

int uIndex;

// int i = 0;

for (int i = 0; i < usDataLen; i++) {

uIndex = (uchCRCHi ^ puchMsg[i]) & 0xff;

uchCRCHi = (byte) (uchCRCLo ^ auchCRCHi[uIndex]);

uchCRCLo = auchCRCLo[uIndex];

}

value = ((((int) uchCRCHi) << 8 | (((int) uchCRCLo) & 0xff))) & 0xffff;

return;

}

public void reset() {

value = 0;

uchCRCHi = (byte) 0xff;

uchCRCLo = (byte) 0xff;

}

public int getValue() {

return value;

}

private static byte uniteBytes(byte src0, byte src1) {

byte _b0 = Byte.decode("0x" + new String(new byte[] { src0 }))

.byteValue();

_b0 = (byte) (_b0 << 4);

byte _b1 = Byte.decode("0x" + new String(new byte[] { src1 }))

.byteValue();

byte ret = (byte) (_b0 ^ _b1);

return ret;

}

private static byte[] HexString2Buf(String src) {

int len = src.length();

byte[] ret = new byte[len / 2+2];

byte[] tmp = src.getBytes();

for (int i = 0; i < len; i += 2) {

ret[i / 2] = uniteBytes(tmp[i], tmp[i + 1]);

}

return ret;

}

public static byte[] getSendBuf(String toSend){

byte[] bb = HexString2Buf(toSend);

CRC16 crc16 = new CRC16();

crc16.update(bb, bb.length-2);

int ri = crc16.getValue();

bb[bb.length-1]=(byte) (0xff & ri);

bb[bb.length-2]=(byte) ((0xff00 & ri) >> 8);

return bb;

}

public static boolean checkBuf(byte[] bb){

CRC16 crc16 = new CRC16();

crc16.update(bb, bb.length-2);

int ri = crc16.getValue();

if(bb[bb.length-1]==(byte)(ri&0xff)

&& bb[bb.length-2]==(byte) ((0xff00 & ri) >> 8))

return true;

return false;

}

public static String getBufHexStr(byte[] raw){

if ( raw == null ) {

  return null;

}

final StringBuilder hex = new StringBuilder( 2 * raw.length );

for ( final byte b : raw ) {

  hex.append(HEXES.charAt((b & 0xF0) >> 4))

    .append(HEXES.charAt((b & 0x0F)));

}

return hex.toString().toLowerCase();

}

/****

• 得到CRC验证

• @param tt

• @return

*/

public static String getCrc(String  tem){

//  String tem="";

//  for(int i=0;i

//  tem+=tt[i];

//  System.out.println("这是传入的值"+tt[i]);

//  }

byte[] sbuf = CRC16.getSendBuf(tem);

System.out.println("这是得到的crc"+CRC16.getBufHexStr(sbuf));

return CRC16.getBufHexStr(sbuf).substring(12, 16).toLowerCase();

}

/**得到要发送的数据

• @param args

*/

public  static String getSendData(String  [] tt)  {

String tem="";

for(int i=0;i

tem+=tt[i];

}

byte[] sbuf = CRC16.getSendBuf(tem);

return CRC16.getBufHexStr(sbuf);

}

public static byte[] getSendBuf2(String  [] tt){

String tem="";

for(int i=0;i

tem+=tt[i];

}

byte[] bb = HexString2Buf(tem);

CRC16 crc16 = new CRC16();

crc16.update(bb, bb.length-2);

int ri = crc16.getValue();

bb[bb.length-1]=(byte) (0xff & ri);

bb[bb.length-2]=(byte) ((0xff00 & ri) >> 8);

return bb;

}

public static void main(String[] args) {

// TODO Auto-generated method stub

//0103040a3d3fb739a1----sendB

//010304b8523ffeef32----sendB

byte[] sbuf = CRC16.getSendBuf("0103040a3d3fb7");

System.out.println(CRC16.getBufHexStr(sbuf));

}

}

Test代码如下：

package oldTest;

import java.io.Flushable;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.Enumeration;

import java.util.Random;

import javax.comm.CommPortIdentifier;

import javax.comm.SerialPort;

public class Test {

static Enumeration portList;

static CommPortIdentifier portId;

static SerialPort serialPort;

static OutputStream outputStream;

static InputStream inputStream;

static String nodeIdx="";

static String crc="";

public static StringBuffer open()throws Exception {

CommPortIdentifier commportidentifier = CommPortIdentifier

.getPortIdentifier("COM1");

serialPort = (SerialPort) commportidentifier.open("scy app", 80);

outputStream = serialPort.getOutputStream();

inputStream = serialPort.getInputStream();

InputStream input = serialPort.getInputStream();

while (true) {

StringBuffer content = new StringBuffer();

int i = 0;

String tag = "";

String crcCode1 = "";

String[] inputString = new String[6];

String crcCode2 = "";

String tempString = "";

serialPort.setInputBufferSize(8);

while (i < 8) {

if (i < 6) {

tempString = Integer.toHexString(input.read());

if (tempString.length() < 2) {

tempString = "0" + tempString;

}

inputString[i] = tempString;

// inputString[0];得到站点名称

nodeIdx = inputString[0];

// inputString[2] + inputString[3];得到检测指标

tag = inputString[2] + inputString[3];

content.append(tempString);

System.out.println("==这是数据段"+content);

} else {

if (i == 6) {// 得到Crc值的前两位

crcCode1 = Integer.toHexString(input.read());

if (crcCode1.length() < 2) {

crcCode1 = "0" + crcCode1;

}

}

if (i == 7) {// 得到Crc值的后两位

crcCode2 = Integer.toHexString(input.read());

if (crcCode2.length() < 2) {

crcCode2 = "0" + crcCode2;

}

}

crc=crcCode1+crcCode2;

System.out.println("==这是crc"+crc);

}

i++;

}

if (CRC16.getCrc(content.toString()).equals(crc)) {

// System.out.println(crcCode1 + crcCode2 + "得到的数据段正确"

// + CRC16.getCrc(inputString));

String nodeName = "";

if (nodeIdx.equals("01")) {

nodeName = "监测站点1";

checkNode(tag, nodeName);

} else {

System.out.println("这也许是监测站点2的站点");

nodeName = "监测站点2";

checkNode(tag, nodeName);

}

} else {

System.out.println(crc + "得到的数据段不正确"

• CRC16.getCrc(content.toString()));

}

}

}

public static void main(String[] args) {

try {

open();

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static void checkNode(String tag, String nodeName) {

if (tag.equals("012c")) {

// System.out.println("这是说明要查悬浮物");

sendData(nodeName, "悬浮物");

} else if (tag.equals("0064")) {

// System.out.println("这是说明要查PH值");

sendData(nodeName, "PH值");

} else if (tag.equals("0b54")) {

// System.out.println("这是说明要查氨氮");

sendData(nodeName, "氨氮");

} else if (tag.equals("0d48")) {

sendData(nodeName, "污水总量");

} else if (tag.equals("0000")) {

sendData(nodeName, "污水总量");

} else if (tag.equals("01f4")) {

sendData(nodeName, "COD");

} else {

// System.out.println(tag + "这个tag不知道是啥");

}

}

public static int getRandom(int min, int max) {

Random random = new Random();

int s = random.nextInt(max) % (max - min + 1) + min;

return s;

}

public static int getRandomEnd() {

int max = 99;

int min = 01;

Random random = new Random();

int s = random.nextInt(max) % (max - min + 1) + min;

return s;

}

public static float getFloatNum(int min, int max) {

return Float.valueOf(getRandom(min, max) + "." + getRandomEnd());

}

public static void sendData(String nodeName, String tagName) {

DB db = new DB();

try {

Float ff = 0f;

//  ff = db.onSelect(nodeName, tagName);

ff=getFloatNum(1,99);

java.text.NumberFormat formater = java.text.DecimalFormat

.getInstance();

String[] totalTemp = new String[7];

if (nodeName.equals("检测站点1")) {

totalTemp[0] = "01";

// if(tagName.equals("COD")){

// ff=15f;

// }else{

// ff=11f;

// }

} else {

totalTemp[0] = "02";

}

formater.setMaximumFractionDigits(2);

formater.setMinimumFractionDigits(2);

ff = Float.valueOf(formater.format(ff));

System.out.println("查询完毕," + tagName + "值为:" + ff);

int fi = Float.floatToRawIntBits(ff);

String num = Integer.toHexString(fi).toString();

if (!num.equals("0")) {

totalTemp[1] = "03";

totalTemp[2] = "04";

totalTemp[4] = num.substring(6, 8);

totalTemp[3] = num.substring(4, 6);

totalTemp[6] = num.substring(2, 4);

totalTemp[5] = num.substring(0, 2);

} else {

totalTemp[1] = "03";

totalTemp[2] = "04";

totalTemp[4] = "00";

totalTemp[3] = "00";

totalTemp[6] = "00";

totalTemp[5] = "00";

}

byte[] sendB = CRC16.getSendBuf2(totalTemp);

outputStream.write(sendB);

outputStream.flush();

outputStream.close();

System.out.println("发送完毕");

} catch (Exception e) {

e.printStackTrace();

} finally {

db.close();

}

}

}

DB类如下：

package oldTest;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Calendar;

import java.util.Random;

public class DB {

private Connection con;

private Statement sta;

private ResultSet res;

private String driverName = "com.microsoft.jdbc.sqlserver.SQLServerDriver"; // 加载JDBC驱动

private String dbURL = "jdbc:sqlserver://localhost:1433; DatabaseName=MonitoringSystem"; // 连接服务器和数据库sample

private String userName = "sa"; // 默认用户名

private String userPwd = ""; // 密码

public DB() {

try {

Class.forName(driverName);

con = DriverManager.getConnection(dbURL, userName, userPwd);

// System.out.println("Connection Successful!"); // 如果连接成功

// 控制台输出Connection

// Successful!

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static int getRandom(int min, int max) {

Random random = new Random();

int s = random.nextInt(max) % (max - min + 1) + min;

return s;

}

public static int getRandomEnd() {

int max = 99;

int min = 01;

Random random = new Random();

int s = random.nextInt(max) % (max - min + 1) + min;

return s;

}

public static float getFloatNum(int min, int max) {

return Float.valueOf(getRandom(min, max) + "." + getRandomEnd());

}

public static float getCFZ() {

return getFloatNum(40, 48);

}

public static float getCY() {

return getFloatNum(100, 110);

}

/***

• 得到N条记录

• @param tagName

• @return

*/

public Float onSelect(String nodeName, String tagName) {

Float ff = 0f;

String sql = "select * from DQYT_MacamCore.dbo.tpoints where name='"

• tagName + "' and fullname like '%" + nodeName + "%'";

try {

sta = con.createStatement();

res = sta.executeQuery(sql);

while (res.next()) {

int tagid = res.getInt("tagId");

String name = res.getString("Name");

String sql2 = "select top 1 * from DQYT_MacamHisData.dbo."

• getTBName() + " where tagid=" + tagid

• " order by idx desc ";

// System.out.println(sql2);

ResultSet rs2;

Statement sta2 = null;

sta2 = con.createStatement();

rs2 = sta2.executeQuery(sql2);

if (tagName.equals("污水总量")) {

String sql3 = "insert into MonitoringSystem.dbo.UploadInfo values("

• tagid

• ",'"

• name

• "',"

• ff

• ",'"

• getEndTime() + "')";

System.out.println(sql3);

Statement sta3 = null;

sta3 = con.createStatement();

sta3.executeUpdate(sql3);

return ff;

} else {

if (name.equals(tagName)) {

while (rs2.next()) {

if (nodeName.equals("监测站点1")) {

if (rs2.getFloat(4) >= 50) {

ff = getCFZ();

} else {

ff = rs2.getFloat(4);

}

} else if (nodeName.equals("监测站点2")) {

if (rs2.getFloat(4) >= 120) {

ff = getCY();

} else {

ff = rs2.getFloat(4);

}

}

String sql3 = "insert into MonitoringSystem.dbo.UploadInfo values("

• tagid

• ",'"

• name

• "',"

• ff

• ",'"

• getEndTime() + "')";

System.out.println(sql3);

Statement sta3 = null;

sta3 = con.createStatement();

sta3.executeUpdate(sql3);

return ff;

}

}

}

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return 0f;

}

/***

• 根据站点名称，得到其污水总量

• @param tagName

• @return

*/

public Float getTagAndTypeLayerId(String nodeName, String tagName) {

String sql = "select * from DQYT_MacamCore.dbo.tpoints where name='"

• tagName + "' and fullname like '%" + nodeName + "%'";

try {

sta = con.createStatement();

res = sta.executeQuery(sql);

// System.out.println(sql);

while (res.next()) {

int tagid = res.getInt("tagId");

String name = res.getString("Name");

String errorAmount = getErrorAmount(res.getInt("nodeIdx"));

Long tSewage = getTSewage(tagid);

ResultSet rs2;

Statement sta2 = null;

sta2 = con.createStatement();

sql = "insert into MonitoringSystem.dbo.UploadInfo values("

• tagid

• ",'"

• name

• "',"

• Float

.valueOf((Long.parseLong(errorAmount) + tSewage))

• ",'" + getEndTime() + "')";

sta2.executeUpdate(sql);

return Float.valueOf((Long.parseLong(errorAmount) + tSewage));

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return null;

}

/***

• 得到污水总量

• @param tagId

• @return

*/

public Long getTSewage(int tagId) {

try {

String sql = "select sum(tSewage) from MonitoringSystem.dbo.TotalSewage where tagId="

• tagId;

sta = con.createStatement();

res = sta.executeQuery(sql);

if (res.next()) {

Long tSewage = res.getLong(1);

return tSewage;

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return new Long(0);

}

/***

• 得到该站点的误差值

• @param typeLayerIdx

• @return

*/

public String getErrorAmount(int typeLayerIdx) {

try {

String sql = "select * from MonitoringSystem.dbo.SiteMessage where typeLayerIdx="

• typeLayerIdx;

sta = con.createStatement();

res = sta.executeQuery(sql);

while (res.next()) {

String errorAmount = res.getString("errorAmount");

return errorAmount;

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (Exception ee) {

ee.printStackTrace();

}

return "0";

}

public void close() {

try {

if (sta != null) {

sta.close();

}

if (con != null) {

con.close();

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public String getTBName() {

java.util.Date d = new java.util.Date();

java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat();

sdf.applyPattern("yyyyMMdd");

String table = "THisData" + sdf.format(d);

table = "THisData20091218";

return table;

}

public String getStartTime() {

java.util.Date d = new java.util.Date();

Calendar cal1 = Calendar.getInstance();

// cal1.set(2010, 04, 21);

d.setMinutes(d.getMinutes() - 1);

java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat();

sdf.applyPattern("yyyy-MM-dd HH:mm");

String ttime = sdf.format(d.getTime());

return ttime;

}

public static String getEndTime() {

java.util.Date d = new java.util.Date();

Calendar cal1 = Calendar.getInstance();

// cal1.set(2010, 04, 21);

java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat();

sdf.applyPattern("yyyy-MM-dd HH:mm");

String ttime = sdf.format(d.getTime());

return ttime;

}

public static void main(String[] args) {

DB db = new DB();

db.onSelect("监测站点1", "COD");

}

}

本文题目：Java中ModBus的使用方法
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