JasperReport usage

jasperreport tools enhance and solve the report issue for your web

一.设计jasperreport报表,编译jasperreport的jasper文件,制作jasper文件用的是IReport的一个工具.基本流程就是:
1.建立数据库连接,我们使用了mysql的数据库
2.利用向导生成xml文件.向导上的内容比较简单清楚,关键是字段的引用.
3.保存后,编译可以得到jasper文件,运行可以看到效果.

二.加入应用

一个很简单的测试.在我们自己的项目中加入报表功能.大致步骤如下:
1.将相关的库放入项目的lib目录,这些库包括jasperreports.jar,bsh.jar,itext.jar
2.在web应用的根目录下建立Reports目录,将刚刚生成的jasper文件拷贝至该文件夹.
3.建立一个网页,作一个有提交按钮的简单网页即可.提交后由servlet处理.
4.servlet的内容: 以下只写了doGet的函数

java 代码

package com.aaron.kemet.servlet;

import java.io.File;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JasperRunManager;

/**
 *
 * @author Aaron
 * JasperReport
 *
 */
public class ReportServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("application/pdf");
        response.setHeader("Content-disposition","inline; filename=classic.pdf" );
        Connection conn = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection("jdbc:mysql://localhost/maxtor","nike", "bogie");
            ServletContext servletContext = this.getServletContext();
            File reportFile = new File(servletContext.getRealPath("Report/classic.jasper"));
            Map<String,Integer> parameters = new HashMap<String,Integer>();
            Integer i=new Integer(1);
            parameters.put("JPID", i);
            byte[] bytes = JasperRunManager.runReportToPdf(reportFile.getPath(), parameters, conn);

            response.setContentLength(bytes.length);
            ServletOutputStream ouputStream = response.getOutputStream();
            ouputStream.write(bytes, 0, bytes.length);
            ouputStream.flush();
            ouputStream.close();
        } catch (JRException jre) {
            System.out.println("JRException:" + jre.getMessage());
        } catch (Exception e) {
            System.out.println("Exception:" + e.getMessage());
        }
    }
}

6.ok,Start Tomcat6   http://localhost:8080/keb/ReportServlet