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Java中串行接口調(diào)用優(yōu)化方式

更新時(shí)間：2024年05月13日 09:23:40 作者：ZerahMu

這篇文章主要介紹了Java中串行接口調(diào)用優(yōu)化方式,具有很好的參考價(jià)值,希望對(duì)大家有所幫助,如有錯(cuò)誤或未考慮完全的地方,望不吝賜教

Java串行接口調(diào)用優(yōu)化

準(zhǔn)備面試總結(jié)下

1.CompletableFuture

 static ThreadPoolExecutor poolExecutor = new ThreadPoolExecutor(10, 20, 1000L, TimeUnit.MICROSECONDS, new ArrayBlockingQueue<>(100));
 
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        CompletableFuture<Integer> task1 = CompletableFuture.supplyAsync(() -> {
            try {
                System.out.println("task1");
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
            return 1000;
        }, poolExecutor);
 
        CompletableFuture<Integer> task2 = CompletableFuture.supplyAsync(() -> {
            try {
                System.out.println("task2");
                Thread.sleep(2000);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
            return 2000;
        }, poolExecutor);
 
 
        CompletableFuture<Integer> task3 = CompletableFuture.supplyAsync(() -> {
            try {
                System.out.println("task3");
                Thread.sleep(10000);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
            return 5000;
        }, poolExecutor);
        Integer result1 = task1.get();
        System.out.println(result1);
        Integer result2 = task2.get();
        System.out.println(result2);
        Integer result3 = task3.get();
        System.out.println(result3);
        CompletableFuture<Void> voidCompletableFuture = CompletableFuture.allOf(task1, task2, task3);
        poolExecutor.shutdown();
        System.out.println("執(zhí)行完畢");
 
    }

2.CoutDownLatch

static HashMap<String, Integer> map = new HashMap<String, Integer>();
 
    public static void main(String[] args) throws InterruptedException, ExecutionException {
        ThreadPoolExecutor poolExecutor = new ThreadPoolExecutor(10, 20, 1000L, TimeUnit.MICROSECONDS, new ArrayBlockingQueue<>(100));
        CountDownLatch countDownLatch = new CountDownLatch(3);
 
 
        Future<Integer> task1 = poolExecutor.submit(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {
                System.out.println("任務(wù)1");
                Thread.sleep(1000);
                System.out.println("任務(wù)1結(jié)束");
                countDownLatch.countDown();
                return 1000;
            }
        });
 
        Future<Integer> task2 = poolExecutor.submit(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {
                System.out.println("任務(wù)2");
                Thread.sleep(500);
                System.out.println("任務(wù)2結(jié)束");
                countDownLatch.countDown();
                return 500;
            }
        });
 
        Future<Integer> task3 = poolExecutor.submit(new Callable<Integer>() {
            @Override
            public Integer call() throws Exception {
                System.out.println("任務(wù)3");
                Thread.sleep(2000);
                System.out.println("任務(wù)3結(jié)束");
                countDownLatch.countDown();
                return 2000;
            }
        });
        map.put("task1", task1.get());
        map.put("task2", task1.get());
        map.put("task3", task1.get());
 
 
        System.out.println("線程跑完了");
        countDownLatch.await();
        System.out.println("---------------任務(wù)執(zhí)行結(jié)束-------------");
        poolExecutor.shutdown();
 
    }

3.阻塞獲取異步調(diào)用結(jié)果

   public static void main(String[] args) throws ExecutionException, InterruptedException {
        ExecutorService executorService = Executors.newFixedThreadPool(3);
        Future<String> submit = executorService.submit(new Callable<String>() {
            @Override
            public String call() throws Exception {
                Thread.sleep(1000);
                return "Its done";
            }
        });
        while (true){
            if (submit.isDone()){
                System.out.println(submit.get());
                break;
            }
            System.out.println(submit.isDone());
 
        }
    }

4.除了上面兩個(gè)方法還有 CyclicBarrier，Semaphore也都可以實(shí)現(xiàn)，可以自己嘗試下

Java串口程序的調(diào)用

RXTX串口插件的使用方法（windows平臺(tái)）

1、把rxtxParallel.dll、rxtxSerial.dll拷貝到：C:\WINDOWS\system32下。

2、如果是在開(kāi)發(fā)的時(shí)候(JDK),需要把RXTXcomm.jar、rxtxParallel.dll、rxtxSerial.dll拷貝到…\jre…\lib\ext下；如：D:\Program Files\Java\jre1.6.0_02\lib\ext

3、需要選中項(xiàng)目右鍵->Preperties->Java Build Path->Libraries->選擇External Folder–>選擇RXTXcomm.jar.

拷貝 RXTXcomm.jar 到 <JAVA_HOME>\jre\lib\ext目錄中；
拷貝 rxtxSerial.dll 到 <JAVA_HOME>\jre\bin目錄中；
拷貝 rxtxParallel.dll 到 <JAVA_HOME>\jre\bin目錄中；

其中<JAVA_HOME>為jdk安裝路徑

下面是一些程序運(yùn)行測(cè)試寫(xiě)的方法

package com.serialport;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Date;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.TooManyListenersException;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

import com.readtable.HexTest;

import gnu.io.CommPort;
import gnu.io.CommPortIdentifier;
import gnu.io.PortInUseException;
import gnu.io.SerialPort;
import gnu.io.SerialPortEvent;
import gnu.io.SerialPortEventListener;
import gnu.io.UnsupportedCommOperationException;

/**
 * 這個(gè)是一個(gè)更加完善的串口調(diào)用及接收函數(shù)類(lèi)
 * @author Administrator
 *
 */
public class SerialReceiver extends Thread implements SerialPortEventListener{
  HexTest hexT2 = new HexTest();
  
  
  	 
  static CommPortIdentifier portId; // 串口通信管理類(lèi)
  static Enumeration<?> portList; // 有效連接上的端口的枚舉
  static InputStream inputStream; //從串口來(lái)數(shù)據(jù)的輸入流
  static OutputStream outputStream;// 向串口輸出的流
  static SerialPort serialPort; // 串口的引用
  
  private static byte[] readBuffer = new byte[1024]; // 4k的buffer空間,緩存串口讀入的數(shù)據(jù) 
  int numBytes;  //buffer中的實(shí)際數(shù)據(jù)字節(jié)數(shù) ，每一次讀取的字節(jié)數(shù)據(jù) 
  // 堵塞隊(duì)列用來(lái)存放讀到的數(shù)據(jù)
  private BlockingQueue<String> msgQueue = new LinkedBlockingQueue<String>();

 
  //其他的常量設(shè)置
  //端口是否打開(kāi)了  
  boolean isOpen = false;  
  // 端口讀入數(shù)據(jù)事件觸發(fā)后,等待n毫秒后再讀取,以便讓數(shù)據(jù)一次性讀完  
  public static int PARAMS_DELAY = 1000; // 延時(shí)等待端口數(shù)據(jù)準(zhǔn)備的時(shí)間  
  public static int PARAMS_TIMEOUT = 2000; // 超時(shí)時(shí)間  
  public static String PARAMS_PORT = "COM4"; // 端口名稱(chēng)  
  public static int PARAMS_RATE = 2400; // 波特率  
  public static int PARAMS_DATABITS = 8; // 數(shù)據(jù)位  
  public static int PARAMS_STOPBITS = 1; // 停止位  
  public static int PARAMS_PARITY = 1; // 奇偶校驗(yàn)  
  

  /**
   * SerialPort EventListene 的方法,持續(xù)監(jiān)聽(tīng)端口上是否有數(shù)據(jù)流
   */
	@Override
	public void serialEvent(SerialPortEvent event) {
		// TODO Auto-generated method stub
		switch (event.getEventType()) {
        case SerialPortEvent.DATA_AVAILABLE:// 當(dāng)有可用數(shù)據(jù)時(shí)讀取數(shù)據(jù)
    	  receTest();     
          break;
      }
	}
	
	/**
	 * 接收的數(shù)據(jù)進(jìn)行打印測(cè)試
	 */
	private void receTest() {

	    try {
              numBytes = 0;
              while (inputStream.available() > 0) {            	 
                  numBytes += inputStream.read(readBuffer,numBytes,1024);
              }

                if (numBytes > 0) {
                    msgQueue.add(new Date() +"方法2接收的字節(jié)數(shù)為："+numBytes+ "   收到的數(shù)據(jù)為：-----"
                    		+ hexT2.arrayToHexStr(readBuffer, 0, numBytes));
                    readBuffer = new byte[1024];  //重新構(gòu)造緩沖對(duì)象，否則有可能會(huì)影響接下來(lái)接收的數(shù)據(jù)
                } else {
                    msgQueue.add("額------沒(méi)有讀到數(shù)據(jù)");
                }
            
        } catch (IOException e) {
        	
        }
	
	}
	
	
	
	/**
	 * 根據(jù)串口名，獲取串口接口
	 * @param portName
	 * @return
	 */
	public SerialPort OpenSerialPort(String portName) {
		 //獲取設(shè)備上的所有端口
	      portList = CommPortIdentifier.getPortIdentifiers();

	      while (portList.hasMoreElements()) {
	          // 獲取相應(yīng)串口對(duì)象
	          portId = (CommPortIdentifier) portList.nextElement();
	          
	          System.out.println("設(shè)備類(lèi)型：--->" + portId.getPortType());
	          System.out.println("設(shè)備名稱(chēng)：--->" + portId.getName());
	          
	          //判斷端口類(lèi)型是否為串口
	          if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {

	              // 判斷如果輸入的串口名對(duì)應(yīng)的串口存在，就打開(kāi)該串口
	              if (portId.getName().equals(portName)) {
	                  try {
	                      // 打開(kāi)串口名字為COM_4(名字任意),延遲為2毫秒
	                      serialPort = (SerialPort) portId.open("COM_3", 2000);
                          return serialPort;
	                  } catch (PortInUseException e) {
	                      e.printStackTrace();
	                      return null;
	                  }
	                  
	              }
	          
	          }
	       }
	      return null;
	      
	}
	
	/**
	 * 打開(kāi)串口的函數(shù)
	 * @param portName  串口名
	 * @param bitrate   波特率
	 * @param databit   數(shù)據(jù)位
	 * @param stopbit   停止位
	 * @param parity    校驗(yàn)方式：奇 偶 無(wú)
	 * @return
	 */
	public int OpenComport(String portName,int bitrate,int databit,int stopbit,int parity) {
		serialPort = OpenSerialPort(portName);
		if(serialPort != null) {
			// 設(shè)置當(dāng)前串口的輸入輸出流
            try {
                inputStream = serialPort.getInputStream();
                outputStream = serialPort.getOutputStream();
            } catch (IOException e) {
                e.printStackTrace();
                return 0;
            }
            // 給當(dāng)前串口添加一個(gè)監(jiān)聽(tīng)器
            try {
                serialPort.addEventListener(this);
            } catch (TooManyListenersException e) {
                e.printStackTrace();
                return 0;
            }
            // 設(shè)置監(jiān)聽(tīng)器生效，即：當(dāng)有數(shù)據(jù)時(shí)通知
            serialPort.notifyOnDataAvailable(true);
            
            //給串口設(shè)置一些參數(shù)
            try {
                // 比特率、數(shù)據(jù)位、停止位、奇偶校驗(yàn)位
                serialPort.setSerialPortParams( bitrate,databit,stopbit,parity);
            } catch (UnsupportedCommOperationException e) {
                e.printStackTrace();
                return 0;
            }

            return 1;
		}
		
		return 0;
	}
	

	
	@Override
	public void run() {
		// TODO Auto-generated method stub
		 try {
	            System.out.println("--------------任務(wù)處理線程運(yùn)行了--------------");
	            while (true) {
	                //如果堵塞隊(duì)列中存在數(shù)據(jù)就將其輸出
	                if (msgQueue.size() > 0) {
	                    System.out.println(msgQueue.take());
	                }
	            }
	        } catch (InterruptedException e) {
	            // TODO Auto-generated catch block
	            e.printStackTrace();
	        }
	}
	
	 public static void main(String[] args) {
		 
		    SerialReceiver cRead = new SerialReceiver();
		    
		    PARAMS_PORT = "COM3"; // 端口名稱(chēng)  
		    PARAMS_RATE = 2400; // 波特率  
		    PARAMS_DATABITS = SerialPort.DATABITS_8;  //數(shù)據(jù)位
		    PARAMS_STOPBITS = SerialPort.STOPBITS_1; // 停止位             
		    PARAMS_PARITY =  SerialPort.PARITY_EVEN; // 奇偶校驗(yàn)
		    
	        int i = cRead.OpenComport(PARAMS_PORT,PARAMS_RATE,PARAMS_DATABITS,
	        		                  PARAMS_STOPBITS,PARAMS_PARITY);
	        if (i == 1) {
	            // 啟動(dòng)線程來(lái)處理收到的數(shù)據(jù)
	        	 cRead.start();
	            try {
	            	
	            	//發(fā)送指令
	            	HexTest hexT = new HexTest();
	        		byte[] bst = hexT.ReadTable07(1,1, 0,3);
	            	outputStream.write(bst, 0,bst.length);

	            } catch (IOException e) {
	                // TODO Auto-generated catch block
	                e.printStackTrace();
	            }
	        } else {
	            return;
	        }
	        
	 }	


}