分两种方法
第一种
1.模版
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE jasperReport PUBLIC "//JasperReports//DTD Report Design//EN""http://jasperreports.sourceforge.net/dtds/jasperreport.dtd"><jasperReport name="DBReport"> <parameter name="hp" class="java.lang.Integer"></parameter> <queryString> <![CDATA[ select tb.name as name,tb.age as age,tbs.marks as marks from jaspertb tb join jaspertbs tbs on(tb.id = tbs.tbid) where tb.id > $P{hp} ]]> </queryString> <field name="marks" class="java.lang.Integer"></field> <field name="name" class="java.lang.String"></field> <field name="age" class="java.lang.Integer"></field> <pageHeader> <band height="30"> <staticText> <reportElement x="0" y="0" width="69" height="24" /> <text><![CDATA[marks:]]></text> </staticText> <staticText> <reportElement x="140" y="0" width="79" height="24" /> <text><![CDATA[name:]]></text> </staticText> <staticText> <reportElement x="280" y="0" width="69" height="24" /> <text><![CDATA[age:]]></text> </staticText> <staticText> <reportElement x="420" y="0" width="69" height="24" /> <text><![CDATA[you don't see this]]></text> </staticText> </band> </pageHeader> <detail> <band height="30"> <textField> <reportElement x="0" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.Integer"> <![CDATA[$F{marks}]]> </textFieldExpression> </textField> <textField> <reportElement x="140" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.String"> <![CDATA[$F{name}]]> </textFieldExpression> </textField> <textField> <reportElement x="280" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.Integer"> <![CDATA[$F{age}]]> </textFieldExpression> </textField> <staticText> <reportElement x="420" y="0" width="69" height="24" /> <text><![CDATA[If you don't see this, it didn't work]]></text> </staticText> </band> </detail></jasperReport>
2.把上面的JRXML文件生成JASPER文件，方便在WEB里面的调用（可以用下面的方法先生成好，放到你知道的文件夹下面）
JasperCompileManager.compileReportToFile("WebRoot\\report\\JasperReportSQL.xml","WebRoot\\report\\JasperReportSQL.jasper");
3.写Servlet调用
import java.io.IOException;import java.io.InputStream;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.HashMap;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;public class DynamicCreateReportWithServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Connection connection = null; //获得输出流 ServletOutputStream servletOutputStream = response.getOutputStream(); //获得JASPER文件的输入流,一定要知道你的文件的地方 InputStream is = getServletConfig().getServletContext().getResourceAsStream("report\\JasperReportSQL.jasper"); //生成Map对象传数据 HashMap hm = new HashMap(); hm.put("hp", new Integer(3)); try { //连结JDBC Class.forName("com.mysql.jdbc.Driver"); connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/jasperreportdb","root", "root"); //生成相于的PDF输入流,这个JasperRunManager对象还有很多种方法的,这只是一种 JasperRunManager.runReportToPdfStream(is,servletOutputStream,hm, connection); //设置格式 response.setContentType("application/pdf"); servletOutputStream.flush(); servletOutputStream.close(); connection.close(); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } catch (JRException e) { e.printStackTrace(); } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); }}
第二种方法
1.这种方法JRXML文件里面不用写SQL
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE jasperReport PUBLIC "//JasperReports//DTD Report Design//EN""http://jasperreports.sourceforge.net/dtds/jasperreport.dtd"><jasperReport name="DBReport"> <field name="id" class="java.lang.Integer"></field> <field name="name" class="java.lang.String"></field> <field name="marks" class="java.lang.Integer"></field> <pageHeader> <band height="30"> <staticText> <reportElement x="0" y="0" width="69" height="24" /> <text><![CDATA[id:]]></text> </staticText> <staticText> <reportElement x="140" y="0" width="79" height="24" /> <text><![CDATA[name:]]></text> </staticText> <staticText> <reportElement x="280" y="0" width="69" height="24" /> <text><![CDATA[marks:]]></text> </staticText> <staticText> <reportElement x="420" y="0" width="69" height="24" /> <text><![CDATA[you don't see this]]></text> </staticText> </band> </pageHeader> <detail> <band height="30"> <textField> <reportElement x="0" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.Integer"> <![CDATA[$F{id}]]> </textFieldExpression> </textField> <textField> <reportElement x="140" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.String"> <![CDATA[$F{name}]]> </textFieldExpression> </textField> <textField> <reportElement x="280" y="0" width="69" height="24" /> <textFieldExpression class="java.lang.Integer"> <![CDATA[$F{marks}]]> </textFieldExpression> </textField> <staticText> <reportElement x="420" y="0" width="69" height="24" /> <text><![CDATA[If you don't see this, it didn't work]]></text> </staticText> </band> </detail></jasperReport>
2.同样是用下面的方法生成JASPER文件
JasperCompileManager.compileReportToFile("WebRoot\\report\\JasperReportSQLResult.xml","WebRoot\\report\\JasperReportSQLResult.jasper");
3.写出Servlet
import java.io.IOException;import java.io.InputStream;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 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.JRResultSetDataSource;import net.sf.jasperreports.engine.JasperRunManager;public class DynamicCreateReportWithServletDateSource extends HttpServlet { private static final long serialVersionUID = 1L; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Connection connection = null; Statement statument = null; ResultSet resultSet = null; String sql = "select tb.name as name,tb.age as age,tbs.marks as marks from jaspertb tb join jaspertbs tbs"; ServletOutputStream servletOutputStream = response.getOutputStream(); InputStream is = getServletConfig().getServletContext().getResourceAsStream("report\\JasperReportSQLResult.jasper"); try { Class.forName("com.mysql.jdbc.Driver"); connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/jasperreportdb","root", "root"); statument = connection.createStatement(); resultSet = statument.executeQuery(sql); //这里把ResultSet封装到JRResultSetDataSource对象里面了 JasperRunManager.runReportToPdfStream(is,servletOutputStream,new HashMap(), new JRResultSetDataSource(resultSet)); response.setContentType("application/pdf"); servletOutputStream.flush(); servletOutputStream.close(); connection.close(); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } catch (JRException e) { e.printStackTrace(); } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); }}
注意：JRXML文件里面数据库的字段都是用$F{marks},而parameter是用$P{xxxx}表示的
，而parameter的值都是传过去的那个HashMap里面设置的
相关资源：敏捷开发V1.0.pptx
