BIRT报表一线揭秘2

收到不少人的邮件咨询我能否直接用JAVA设计报表然后直接展示出来，而非运行导出或者生成一个文件，毕竟生成或者导出的文件不是在服务器端就是要客户浏览器接收，不算友好。其实这并非难事，只需把生成的设计文档放在服务器端然后又直接用webviewer打开便是。代码如下：

[java] view plain copy

1. import java.io.IOException;  
2. import javax.servlet.ServletException;  
3. import javax.servlet.annotation.WebServlet;  
4. import javax.servlet.http.HttpServlet;  
5. import javax.servlet.http.HttpServletRequest;  
6. import javax.servlet.http.HttpServletResponse;  
7.   
8. import org.eclipse.birt.core.framework.Platform;  
9. import org.eclipse.birt.report.model.api.CellHandle;  
10. import org.eclipse.birt.report.model.api.DesignConfig;  
11. import org.eclipse.birt.report.model.api.DesignElementHandle;  
12. import org.eclipse.birt.report.model.api.ElementFactory;  
13. import org.eclipse.birt.report.model.api.GridHandle;  
14. import org.eclipse.birt.report.model.api.IDesignEngine;  
15. import org.eclipse.birt.report.model.api.IDesignEngineFactory;  
16. import org.eclipse.birt.report.model.api.ImageHandle;  
17. import org.eclipse.birt.report.model.api.LabelHandle;  
18. import org.eclipse.birt.report.model.api.ReportDesignHandle;  
19. import org.eclipse.birt.report.model.api.RowHandle;  
20. import org.eclipse.birt.report.model.api.SessionHandle;  
21. import org.eclipse.birt.report.model.api.activity.SemanticException;  
22.   
23. import com.ibm.icu.util.ULocale;  
24.   
25. @WebServlet("/SimpleCreate")  
26. public class SimpleCreate extends HttpServlet {  
27.     private static final long serialVersionUID = 1L;  
28.   
29.     public SimpleCreate() {  
30.         super();  
31.     }  
32.   
33.     protected void doGet(HttpServletRequest request,  
34.             HttpServletResponse response) throws ServletException, IOException {  
35.         try  
36.            {  
37.                buildReport(request, response);  
38.            }  
39.            catch( IOException e )  
40.            {  
41.                e.printStackTrace();  
42.            }  
43.            catch( SemanticException e )  
44.            {  
45.                e.printStackTrace();  
46.            }  
47.     }  
48.   
49.       
50.     protected void doPost(HttpServletRequest request,  
51.             HttpServletResponse response) throws ServletException, IOException {  
52.         try  
53.            {  
54.                buildReport(request, response);  
55.            }  
56.            catch( IOException e )  
57.            {  
58.                e.printStackTrace();  
59.            }  
60.            catch( SemanticException e )  
61.            {  
62.                e.printStackTrace();  
63.            }  
64.   
65.     }  
66.   
67.     static void buildReport(HttpServletRequest request,  
68.             HttpServletResponse response) throws IOException, SemanticException {  
69.         DesignConfig config = new DesignConfig();  
70.   
71.         //config.setProperty("BIRT_HOME","D:\\Develop Install Files\\birt-runtime-4_2_1\\ReportEngine");  
72.         IDesignEngine engine = null;  
73.         try {  
74.             Platform.startup(config);  
75.             IDesignEngineFactory factory = (IDesignEngineFactory) Platform  
76.                     .createFactoryObject(IDesignEngineFactory.EXTENSION_DESIGN_ENGINE_FACTORY);  
77.             engine = factory.createDesignEngine(config);  
78.         } catch (Exception ex) {  
79.             ex.printStackTrace();  
80.         }  
81.   
82.         SessionHandle session = engine.newSessionHandle(ULocale.ENGLISH);  
83.         ReportDesignHandle design = session.createDesign();  
84.         ElementFactory efactory = design.getElementFactory();  
85.         DesignElementHandle element = efactory  
86.                 .newSimpleMasterPage("Page Master");  
87.         design.getMasterPages().add(element);  
88.         GridHandle grid = efactory.newGridItem(null, 2 /* cols */, 1 /* row */);  
89.         design.getBody().add(grid);  
90.         grid.setWidth("100%");  
91.           
92.         //在行加入一个图片  
93.         RowHandle row = (RowHandle) grid.getRows().get(0);  
94.         ImageHandle image = efactory.newImage(null);  
95.         CellHandle cell = (CellHandle) row.getCells().get(0);  
96.         cell.getContent().add(image);  
97.         image.setURL("\"https://img-my.youkuaiyun.com/uploads/201301/09/1357690895_3463.png\"");  
98.   
99.         // 产生一个标签  
100.         LabelHandle label = efactory.newLabel(null);  
101.         cell = (CellHandle) row.getCells().get(1);  
102.         cell.getContent().add(label);  
103.         label.setText("测试，用Java生成报表并用报表展示器展示报表");  
104.   
105.         // 保存报表  
106.         String path=request.getSession().getServletContext().getRealPath("/");  
107.         System.out.println(path);  
108.         design.saveAs(path+"/sample.rptdesign");  
109.         design.close();  
110.           
111.         //用报表展示器打开报表  
112.         String reportpath=request.getContextPath();  
113.         System.out.println(reportpath);  
114.         response.sendRedirect(reportpath+"/frameset?__report=sample.rptdesign");          
115.         System.out.println("Finished");  
116.     }  
117.   
118. }  

关键的是最后几步：

保存报表

String path=request.getSession().getServletContext().getRealPath("/");
design.saveAs(path+"/sample.rptdesign");
展示报表

String reportpath=request.getContextPath();
response.sendRedirect(reportpath+"/frameset?__report=sample.rptdesign");

这个servlet运行并直接生成了一个报表sample.rptdesign，并通过报表展示器查看报表

需要在web.xml中加入如下的配置：

<servlet>

<servlet-name>SimpleCreate</servlet-name>

<servlet-class>birt.SimpleCreate</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>SimpleCreate</servlet-name>

<url-pattern>/SimpleCreate</url-pattern>

</servlet-mapping>

我们把他发布到WebViewerExample工程下，访问http://localhost:8080/WebViewerExample/SimpleCreate，控制台会打印出程序中的输出

D:\apache-tomcat-7.0.33\webapps\WebViewerExample\

/WebViewerExample

Finished

注意地址栏上的地址信息是http://localhost:8080/WebViewerExample/frameset?__report=sample.rptdesign，是因为我们在程序中用的response.sendRedirect()方法。