鍍金池/ 問答/數(shù)據(jù)分析&挖掘  Java/ 沒有使用的socket卻出現(xiàn) java.net.SocketException:

沒有使用的socket卻出現(xiàn) java.net.SocketException: Connection reset錯(cuò)誤

我的代碼如下有三個(gè):

1.servlet類

package com.main.web;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.rosuda.REngine.REXP;
import org.rosuda.REngine.Rserve.RConnection;
import org.rosuda.REngine.Rserve.RserveException;
import org.dom4j.Node;
import com.main.service.Execute;

/**
 * Servlet implementation class ExecuteR
 */
@WebServlet("/ExecuteR")
public class ExecuteR extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ExecuteR() {
        super();
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String RSentences=request.getParameter("data");//這個(gè)例子必須到頁(yè)面點(diǎn)擊
        String path=getServletContext().getRealPath("/");
        System.out.println("servlet路徑:"+path);
        Execute wc=new Execute();
        REXP xp;
        try {
            xp = wc.getRobj(path);//獲得R對(duì)象
            wc.createPlot(xp,wc,path);//
        } catch (Exception e) {
            e.printStackTrace();
        }
        
        
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

}

2.Execute.java

package com.main.service;


import java.awt.Graphics;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.HeadlessException;
import java.awt.Image;
import java.awt.MediaTracker;
import java.awt.Toolkit;
import java.awt.Transparency;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import org.dom4j.Node;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;

import org.rosuda.REngine.REXP;
import org.rosuda.REngine.Rserve.RConnection;

import com.main.util.Rservel;
import com.main.service.ReadData;

public class Execute extends JFrame{
private static final long serialVersionUID=1L;
static Image img;
public REXP getRobj(String path) throws Exception{
    System.out.println("getRobj()");
    REXP xp = null;
    try{
    RConnection c=Rservel.getRConnection();
    System.out.println("c=Rservel.getRConnection()......"+c);
    c.setStringEncoding("utf8");//設(shè)置字符編碼
    //返回R的版本
    REXP Rservesion=c.eval("R.version.string");
    System.out.println("執(zhí)行Excute.java路徑:"+System.getProperty("user.dir"));
    System.out.println("---------");
    String item="隸屬度";
    String data=ReadData.testSaxReader(item,path);
    System.out.println(data);
    xp=c.eval("source('"+path+"WEB-INF/data/"+item+".txt')");
    System.out.println(xp);
        
    
    System.out.println(Rservesion.asString());
    xp=c.parseAndEval("jpeg('test.jpg',quality=90)");
    c.eval("library(RColorBrewer)");
    c.eval("H <- c(7,12,28,3,41)");
    c.eval("colors<-brewer.pal(5,'Set1')");
    c.parseAndEval(" barplot(H,rep(1,5),col=colors);dev.off()");
    xp=c.parseAndEval("r=readBin('test.jpg','raw',3000*3000);unlink('test.jpg');r");
    c.close();
    }catch(Exception e){
        System.out.println(e);
    }
    return xp;
}
    
    
    public void createPlot(REXP xp, JFrame f,String path)throws Exception{
        
        try {
            Image image=Toolkit.getDefaultToolkit().createImage(xp.asBytes());
            BufferedImage bufferedImage=toBufferedImage(image);
           ImageIO.write(bufferedImage, "JPG", new File(path+"/images/routput/98.jpg"));//
          
       } catch (IOException e) {
           e.printStackTrace();
       }
    }

    public  BufferedImage toBufferedImage(Image image) {  
        if (image instanceof BufferedImage) {  
            return (BufferedImage)image;  
         }  
         image = new ImageIcon(image).getImage();  
         BufferedImage bimage = null;  
         GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();  
        try {  
             
            int transparency = Transparency.OPAQUE;   
             GraphicsDevice gs = ge.getDefaultScreenDevice();  
             GraphicsConfiguration gc = gs.getDefaultConfiguration();  
             bimage = gc.createCompatibleImage(  
             image.getWidth(null), image.getHeight(null), transparency);  
         } catch (HeadlessException e) {  
         }  
        
        if (bimage == null) {   
            int type = BufferedImage.TYPE_INT_RGB;   
             bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), type);  
         }  
         Graphics g = bimage.createGraphics();  
         g.drawImage(image, 0, 0, null);  
         g.dispose();  
        
        return bimage;  
    } 

}


 

3.ReaderData.java

package com.main.service;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import java.io.PrintWriter;
import org.dom4j.Node;

public class ReadData {
    }
              public static String testSaxReader(String item,String path) throws DocumentException, FileNotFoundException {
                  SAXReader saxReader = new SAXReader();
                  System.out.println("工程路徑:"+System.getProperty("user.dir"));
                  FileInputStream file = new FileInputStream(path+"WEB-INF/upload/0625.Rs");
                  Document doc = saxReader.read(file);
                  Element menu = doc.getRootElement(); //獲取根元素
                  Node person=menu.selectSingleNode("/Menu//Item[@Title='"+item+"']");//
                  File fp=new File(path+"WEB-INF/data/"+item+".txt");
                  PrintWriter pfp= new PrintWriter(fp);
                  pfp.print(person.getText().replace("\n","\r\n"));
                  pfp.close();
                  return person.getText().replace("\n","\r\n");
                  
              }
    
}

代碼運(yùn)行后有以下錯(cuò)誤:

java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(Unknown Source)
    at java.net.SocketInputStream.read(Unknown Source)
    at java.net.SocketInputStream.read(Unknown Source)
    at org.rosuda.REngine.Rserve.protocol.RTalk.request(RTalk.java:213)
    at org.rosuda.REngine.Rserve.protocol.RTalk.request(RTalk.java:180)
    at org.rosuda.REngine.Rserve.protocol.RTalk.request(RTalk.java:250)
    at org.rosuda.REngine.Rserve.RConnection.eval(RConnection.java:231)
    at com.main.service.Execute.getRobj(Execute.java:83)
    at com.main.web.ExecuteR.doGet(ExecuteR.java:45)
    at com.main.web.ExecuteR.doPost(ExecuteR.java:59)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1132)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1539)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1495)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)
org.rosuda.REngine.Rserve.RserveException: eval failed
java.lang.NullPointerException
    at com.main.service.Execute.createPlot(Execute.java:106)
    at com.main.web.ExecuteR.doGet(ExecuteR.java:46)
    at com.main.web.ExecuteR.doPost(ExecuteR.java:59)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:94)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:502)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1132)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1539)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1495)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

請(qǐng)問我是哪方面的問題沒處理好?該怎么處理?

回答
編輯回答
蟲児飛

java.lang.NullPointerException
應(yīng)該是空指針異常引發(fā)的socke錯(cuò)誤,檢查賦值操作為NULL的情況

2017年3月10日 02:17