问题描述

jasperreport+applet实现客户端打印报表

本人使用ireport5.1.0画的报表，实现客户端打印时报java.io.StreamCorruptedException:invalid stream header:0D0A0D0A这个错误，下面是代码，请各位高手帮忙看看怎么回事：
1）、action类代码
import java.io.File;
import java.io.ObjectOutputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

import net.sf.jasperreports.engine.JRResultSetDataSource;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class IreportAction extends ActionSupport{
private static final long serialVersionUID = 1974082731836773155L;
private static final String CONTENTTYPE = "application/octet-stream";

/**
 * 打印报表
 * @return
 */
@SuppressWarnings("unchecked")
public void doIreportPrint(){
    HttpServletResponse response = ServletActionContext.getResponse();
    String fileName = "";
    String sql = "select id,dname,dcode from ct_su_departments where datalevel = 0 and status = 0 and rownum <=100";

    //建立连接
    Connection conn = this.createConnection();

    //参数设置
    Map parameters = new HashMap();

    try {
        Statement stmt = conn.createStatement();//获取数据库链接
        ResultSet rs = stmt.executeQuery(sql);//获取数据
        String jasper = new File(ServletActionContext.getServletContext().getRealPath("/report/report1.jasper")).getPath();//获取文件的绝对路径
        JasperPrint jpt = JasperFillManager.fillReport(jasper, parameters, new JRResultSetDataSource(rs));//匹配数据源，生成JasperPrint
        response.setContentType(CONTENTTYPE);
        ServletOutputStream ouputStream = response.getOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(ouputStream);
        oos.writeObject(jpt);
        oos.flush();
        oos.close();
    }catch(Exception e) {
        System.out.println("Error:" + e.toString());
        e.printStackTrace();
    }finally {
        CloseConnect(conn);
        conn = null;
    }
}

/**
 * 建立数据库连接
 * @return
 */
public Connection createConnection(){
    Connection conn;
    try{
        String driver = "oracle.jdbc.driver.OracleDriver";//oracle.jdbc.OracleDriver
        String url = "jdbc:oracle:thin:@172.19.24.239:1521:NSOA";
        Class.forName(driver);
        conn = DriverManager.getConnection(url,"JXKHOA","JXKHOA");
        conn.setAutoCommit(false);
        return conn;
    }catch(SQLException e1) {
        System.out.println("建立连接错误 = " + e1.toString());
        e1.printStackTrace();
    }catch(ClassNotFoundException e2) {
        System.out.println("建立连接错误 = " + e2.toString());
        e2.printStackTrace();
    }
    return null;
}

/**
 * 关闭数据库连接
 * @param conn
 */
public void CloseConnect(Connection conn){
    try{
        conn.commit();
        conn.setAutoCommit(true);
        conn.close();
    }catch(Exception e){
        System.out.println("关闭连接错误 = " + e.toString());
    }
}

}

2）japplet代码：
import java.io.PrintWriter;
import java.io.StringWriter;
import java.net.URL;

import javax.swing.JOptionPane;

import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperPrintManager;
import net.sf.jasperreports.engine.util.JRLoader;

public class IreportApplet extends javax.swing.JApplet{
private static final long serialVersionUID = 2525694418170444107L;

private URL url = null;
private JasperPrint jasperPrint = null;

public void init(){
    String strUrl = "http://172.19.24.28:8100/BaseWeb/ireportPrint.action";
    if (strUrl != null){
        try{
            URL urll = new URL(strUrl);
            url = urll;
            System.out.println("url="+urll);
        }catch (Exception e){
            StringWriter swriter = new StringWriter();
            PrintWriter pwriter = new PrintWriter(swriter);
            e.printStackTrace(pwriter);
            JOptionPane.showMessageDialog(this, swriter.toString());
        }
    }else{
        JOptionPane.showMessageDialog(this, "init():Source URL not specified");
    }
}

public void start(){
    if (url != null){
        if (jasperPrint == null){
            try{
                jasperPrint = (JasperPrint)JRLoader.loadObject(url);
            }catch (Exception e){
                StringWriter swriter = new StringWriter();
                PrintWriter pwriter = new PrintWriter(swriter);
                e.printStackTrace(pwriter);
                JOptionPane.showMessageDialog(this, swriter.toString());
            }
        }

        if (jasperPrint != null){
            final JasperPrint print = jasperPrint;
            Thread thread = new Thread(new Runnable(){
                public void run(){
                    try{
                        System.out.println("进入start方法，即将打印pdf文件");
                        JasperPrintManager.printReport(print, true);
                    }catch (Exception e){
                        StringWriter swriter = new StringWriter();
                        PrintWriter pwriter = new PrintWriter(swriter);
                        e.printStackTrace(pwriter);
                        JOptionPane.showMessageDialog(null, swriter.toString());
                    }
                }
            });
            thread.start();
        }else{
            JOptionPane.showMessageDialog(this, "Empty report.");
        }
    }else{
        JOptionPane.showMessageDialog(this, "start():Source URL not specified");
    }
}

}

执行到jasperPrint = (JasperPrint)JRLoader.loadObject(url);这就话是就报错了。该报表导出excel和pdf都是可以的，而且在action类里面直接使用JasperViewer.viewReport(jpt,false);也是可以打印的，就这个japplet生成客户端打印时报错了。希望各位高手能赐教，非常感谢！！！

解决方案

新建一 web 项目 Test2。将 iReport 目录 lib 下的所有 jar 包导入。在 servlet 程序中把从数据库得到的数据传入 *.jrxml 文件得到 *.jrprint 文件（这才是我们想要的东西），并把这个对象写入 Stream流，以返还给请求客户端。源码：
?

view plainprint?

package?com.defo......
答案就在这里：Applet+客户端打印+jasperreport+报表