JasperReport学习笔记4-查询数据库生成动态的报表（WEB）

分两种方法 
第一种 
1.模版 

Xml代码  

1. <?xml version="1.0" encoding="UTF-8"?>  
2. <!DOCTYPE jasperReport PUBLIC "//JasperReports//DTD Report Design//EN"  
3. "http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">  
4. <jasperReport name="DBReport">  
5.     <parameter name="hp" class="java.lang.Integer"></parameter>   
6.     <queryString>  
7.         <![CDATA[ 
8.             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 > $P{hp} 
9.         ]]>  
10.     </queryString>  
11.     <field name="marks" class="java.lang.Integer"></field>  
12.     <field name="name" class="java.lang.String"></field>  
13.     <field name="age" class="java.lang.Integer"></field>  
14.     <pageHeader>  
15.         <band height="30">  
16.             <staticText>  
17.                 <reportElement x="0" y="0" width="69" height="24" />  
18.                 <text><![CDATA[marks:]]></text>  
19.             </staticText>  
20.               
21.             <staticText>  
22.                 <reportElement x="140" y="0" width="79" height="24" />  
23.                 <text><![CDATA[name:]]></text>  
24.             </staticText>  
25.               
26.             <staticText>  
27.                 <reportElement x="280" y="0" width="69" height="24" />  
28.                 <text><![CDATA[age:]]></text>  
29.             </staticText>   
30.               
31.             <staticText>  
32.                 <reportElement x="420" y="0" width="69" height="24" />  
33.                 <text><![CDATA[you don't see this]]></text>  
34.             </staticText>       
35.         </band>  
36.     </pageHeader>  
37.       
38.     <detail>  
39.         <band height="30">  
40.             <textField>  
41.                 <reportElement x="0" y="0" width="69" height="24" />  
42.                 <textFieldExpression class="java.lang.Integer">  
43.                     <![CDATA[$F{marks}]]>  
44.                 </textFieldExpression>  
45.             </textField>  
46.             <textField>  
47.                 <reportElement x="140" y="0" width="69" height="24" />  
48.                 <textFieldExpression class="java.lang.String">  
49.                     <![CDATA[$F{name}]]>  
50.                 </textFieldExpression>  
51.             </textField>  
52.             <textField>  
53.                 <reportElement x="280" y="0" width="69" height="24" />  
54.                 <textFieldExpression class="java.lang.Integer">  
55.                     <![CDATA[$F{age}]]>  
56.                 </textFieldExpression>  
57.             </textField>    
58.             <staticText>  
59.                 <reportElement x="420" y="0" width="69" height="24" />  
60.                 <text><![CDATA[If you don't see this, it didn't work]]></text>  
61.             </staticText>  
62.         </band>  
63.     </detail>  
64. </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） 

Java代码  

1. JasperCompileManager.compileReportToFile("WebRoot\\report\\JasperReportSQL.xml","WebRoot\\report\\JasperReportSQL.jasper");  

3.写Servlet调用 

Java代码  

1. import java.io.IOException;  
2. import java.io.InputStream;  
3. import java.sql.Connection;  
4. import java.sql.DriverManager;  
5. import java.sql.SQLException;  
6. import java.util.HashMap;  
7.   
8. import javax.servlet.ServletException;  
9. import javax.servlet.ServletOutputStream;  
10. import javax.servlet.http.HttpServlet;  
11. import javax.servlet.http.HttpServletRequest;  
12. import javax.servlet.http.HttpServletResponse;  
13.   
14. import net.sf.jasperreports.engine.JRException;  
15. import net.sf.jasperreports.engine.JasperRunManager;  
16.   
17. public class DynamicCreateReportWithServlet extends HttpServlet {  
18.   
19.     private static final long serialVersionUID = 1L;  
20.   
21.     public void doGet(HttpServletRequest request, HttpServletResponse response)  
22.             throws ServletException, IOException {  
23.         Connection connection = null;  
24.         //获得输出流  
25.         ServletOutputStream servletOutputStream = response.getOutputStream();  
26.         //获得JASPER文件的输入流,一定要知道你的文件的地方  
27.         InputStream is = getServletConfig().getServletContext().getResourceAsStream("report\\JasperReportSQL.jasper");  
28.         //生成Map对象传数据  
29.         HashMap hm =  new HashMap();  
30.         hm.put("hp", new Integer(3));  
31.         try {  
32.             //连结JDBC  
33.             Class.forName("com.mysql.jdbc.Driver");  
34.             connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/jasperreportdb","root", "root");  
35.             //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  
36.             JasperRunManager.runReportToPdfStream(is,servletOutputStream,hm, connection);  
37.             //设置格式  
38.             response.setContentType("application/pdf");  
39.             servletOutputStream.flush();  
40.             servletOutputStream.close();  
41.             connection.close();  
42.         } catch (ClassNotFoundException e) {  
43.             e.printStackTrace();  
44.         } catch (SQLException e) {  
45.             e.printStackTrace();  
46.         } catch (JRException e) {  
47.             e.printStackTrace();  
48.         }         
49.     }  
50.   
51.     public void doPost(HttpServletRequest request, HttpServletResponse response)  
52.             throws ServletException, IOException {  
53.         this.doGet(request, response);  
54.     }  
55.   
56. }  

第二种方法 
1.这种方法JRXML文件里面不用写SQL 

Xml代码  

1. <?xml version="1.0" encoding="UTF-8"?>  
2. <!DOCTYPE jasperReport PUBLIC "//JasperReports//DTD Report Design//EN"  
3. "http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">  
4. <jasperReport name="DBReport">  
5.     <field name="id" class="java.lang.Integer"></field>  
6.     <field name="name" class="java.lang.String"></field>  
7.     <field name="marks" class="java.lang.Integer"></field>  
8.       
9.     <pageHeader>  
10.         <band height="30">  
11.             <staticText>  
12.                 <reportElement x="0" y="0" width="69" height="24" />  
13.                 <text><![CDATA[id:]]></text>  
14.             </staticText>  
15.               
16.             <staticText>  
17.                 <reportElement x="140" y="0" width="79" height="24" />  
18.                 <text><![CDATA[name:]]></text>  
19.             </staticText>  
20.               
21.             <staticText>  
22.                 <reportElement x="280" y="0" width="69" height="24" />  
23.                 <text><![CDATA[marks:]]></text>  
24.             </staticText>   
25.               
26.             <staticText>  
27.                 <reportElement x="420" y="0" width="69" height="24" />  
28.                 <text><![CDATA[you don't see this]]></text>  
29.             </staticText>       
30.         </band>  
31.     </pageHeader>  
32.       
33.     <detail>  
34.         <band height="30">  
35.             <textField>  
36.                 <reportElement x="0" y="0" width="69" height="24" />  
37.                 <textFieldExpression class="java.lang.Integer">  
38.                     <![CDATA[$F{id}]]>  
39.                 </textFieldExpression>  
40.             </textField>  
41.             <textField>  
42.                 <reportElement x="140" y="0" width="69" height="24" />  
43.                 <textFieldExpression class="java.lang.String">  
44.                     <![CDATA[$F{name}]]>  
45.                 </textFieldExpression>  
46.             </textField>  
47.             <textField>  
48.                 <reportElement x="280" y="0" width="69" height="24" />  
49.                 <textFieldExpression class="java.lang.Integer">  
50.                     <![CDATA[$F{marks}]]>  
51.                 </textFieldExpression>  
52.             </textField>    
53.             <staticText>  
54.                 <reportElement x="420" y="0" width="69" height="24" />  
55.                 <text><![CDATA[If you don't see this, it didn't work]]></text>  
56.             </staticText>  
57.         </band>  
58.     </detail>  
59. </jasperReport>  

2.同样是用下面的方法生成JASPER文件 

Java代码  

1. JasperCompileManager.compileReportToFile("WebRoot\\report\\JasperReportSQLResult.xml","WebRoot\\report\\JasperReportSQLResult.jasper");  

3.写出Servlet 

Java代码  

1. import java.io.IOException;  
2. import java.io.InputStream;  
3. import java.sql.Connection;  
4. import java.sql.DriverManager;  
5. import java.sql.ResultSet;  
6. import java.sql.SQLException;  
7. import java.sql.Statement;  
8. import java.util.HashMap;  
9.   
10. import javax.servlet.ServletException;  
11. import javax.servlet.ServletOutputStream;  
12. import javax.servlet.http.HttpServlet;  
13. import javax.servlet.http.HttpServletRequest;  
14. import javax.servlet.http.HttpServletResponse;  
15.   
16. import net.sf.jasperreports.engine.JRException;  
17. import net.sf.jasperreports.engine.JRResultSetDataSource;  
18. import net.sf.jasperreports.engine.JasperRunManager;  
19.   
20. public class DynamicCreateReportWithServletDateSource extends HttpServlet {  
21.   
22.     private static final long serialVersionUID = 1L;  
23.   
24.     public void doGet(HttpServletRequest request, HttpServletResponse response)  
25.             throws ServletException, IOException {  
26.         Connection connection = null;  
27.         Statement statument = null;  
28.         ResultSet resultSet = null;  
29.         String sql = "select tb.name as name,tb.age as age,tbs.marks as marks from jaspertb tb join jaspertbs tbs";  
30.         ServletOutputStream servletOutputStream = response.getOutputStream();  
31.         InputStream is = getServletConfig().getServletContext().getResourceAsStream("report\\JasperReportSQLResult.jasper");  
32.         try {  
33.             Class.forName("com.mysql.jdbc.Driver");  
34.             connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/jasperreportdb","root", "root");  
35.             statument = connection.createStatement();  
36.             resultSet = statument.executeQuery(sql);  
37.             //这里把ResultSet封装到JRResultSetDataSource对象里面了  
38.             JasperRunManager.runReportToPdfStream(is,servletOutputStream,new HashMap(), new JRResultSetDataSource(resultSet));  
39.             response.setContentType("application/pdf");  
40.             servletOutputStream.flush();  
41.             servletOutputStream.close();  
42.             connection.close();  
43.         } catch (ClassNotFoundException e) {  
44.             e.printStackTrace();  
45.         } catch (SQLException e) {  
46.             e.printStackTrace();  
47.         } catch (JRException e) {  
48.             e.printStackTrace();  
49.         }  
50.     }  
51.   
52.     public void doPost(HttpServletRequest request, HttpServletResponse response)  
53.             throws ServletException, IOException {  
54.         this.doGet(request, response);  
55.     }  
56.   
57. }  

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

转载自：http://langhua9527.iteye.com/blog/400435