根据我的研究,我发现了以下使用方法。这些方法从最直接(简单)的方法开始,涉及较少的前期复杂性/配置,并演变为更加抽象,但对 Spring 的依赖更多/更复杂的 Spring 配置。
方法一:直接在Controller中使用JasperReports API
只需将内容写入 servlet 输出流即可。
@RequestMapping(value = "helloReport1", method = RequestMethod.GET)
@ResponseBody
public void getRpt1(HttpServletResponse response) throws JRException, IOException {
InputStream jasperStream = this.getClass().getResourceAsStream("/jasperreports/HelloWorld1.jasper");
Map<String,Object> params = new HashMap<>();
JasperReport jasperReport = (JasperReport) JRLoader.loadObject(jasperStream);
JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, params, new JREmptyDataSource());
response.setContentType("application/x-pdf");
response.setHeader("Content-disposition", "inline; filename=helloWorldReport.pdf");
final OutputStream outStream = response.getOutputStream();
JasperExportManager.exportReportToPdfStream(jasperPrint, outStream);
}
方法二:将JasperReportPdf视图注入Controller
给定 JasperReportsPdfView bean:
@Bean @Qualifier("helloWorldReport2")
public JasperReportsPdfView getHelloWorldReport() {
JasperReportsPdfView v = new JasperReportsPdfView();
v.setUrl("classpath:jasperreports/HelloWorld2.jasper");
v.setReportDataKey("datasource");
return v;
}
这个视图可以注入或连接到Controller中使用:
@Autowired @Qualifier("helloWorldReport2")
private JasperReportsPdfView helloReport;
@RequestMapping(value = "helloReport2", method = RequestMethod.GET)
public ModelAndView getRpt2(ModelAndView modelAndView) {
Map<String, Object> parameterMap = new HashMap<>();
parameterMap.put("datasource", new JREmptyDataSource());
modelAndView = new ModelAndView(helloReport, parameterMap);
return modelAndView;
}
请注意,使用JasperReportsPdfView(或更通用的JasperReportsMultiFormatView)需要依赖spring-context-support:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>4.1.3</version>
</dependency>
方法 3:使用 XML 或 ResourceBundle 视图解析器将逻辑视图名称映射到 JasperReport 视图
配置一个新的视图解析器,在这种情况下,ResourceBundleViewResolver 在InternalResourceViewResolver 之前运行。这是基于设置的顺序值(0 发生在 1 之前):
@Bean
public ResourceBundleViewResolver getResourceBundleViewResolver() {
ResourceBundleViewResolver resolver = new ResourceBundleViewResolver();
resolver.setBasename("jasperreport-views");
resolver.setOrder(0);
return resolver;
}
@Bean
public InternalResourceViewResolver getInternalResourceViewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
resolver.setOrder(1);
return resolver;
}
然后,在我们的类路径的根目录中,jasperreport-views.properties 文件可以包含逻辑视图名称以及与渲染 JasperReport 相关的类和属性值(即 url 和 reportDataKey):
helloReport3.(class)=org.springframework.web.servlet.view.jasperreports.JasperReportsPdfView
helloReport3.url=classpath:/jasperreports/HelloWorld3.jasper
helloReport3.reportDataKey=myDataSourceKey
控制器代码如下所示:
@RequestMapping(value = "helloReport3", method = RequestMethod.GET)
public ModelAndView getRpt3(ModelMap modelMap, ModelAndView modelAndView) {
modelMap.put("myDataSourceKey", new JREmptyDataSource());
return new ModelAndView("helloReport3", modelMap);
}
我喜欢这种方法。控制器保持“愚蠢”,只处理字符串值,名称到视图的映射可以在一个位置发生。
方法四:使用JasperReportsViewResolver
配置一个零序的JasperReportViewResolver,诀窍是使用setViewNames 告诉 Spring 你希望这个解析器处理哪些逻辑视图名称(否则你最终会得到“无法从类路径资源加载 JasperReports 报告 [ jasperreports/index.jasper]" 类型错误):
@Bean
public JasperReportsViewResolver getJasperReportsViewResolver() {
JasperReportsViewResolver resolver = new JasperReportsViewResolver();
resolver.setPrefix("classpath:/jasperreports/");
resolver.setSuffix(".jasper");
resolver.setReportDataKey("datasource");
resolver.setViewNames("rpt_*");
resolver.setViewClass(JasperReportsMultiFormatView.class);
resolver.setOrder(0);
return resolver;
}
@Bean
public InternalResourceViewResolver getInternalResourceViewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
resolver.setOrder(1);
return resolver;
}
在控制器内部:
@RequestMapping(value = "helloReport4", method = RequestMethod.GET)
public ModelAndView getRpt4(ModelMap modelMap, ModelAndView modelAndView) {
modelMap.put("datasource", getWidgets());
modelMap.put("format", "pdf");
modelAndView = new ModelAndView("rpt_HelloWorld", modelMap);
return modelAndView;
}
这是我的首选方法。控制器解析 jasper 报告的方式与使用 InternalResourceViewResolver 解析 jsp 视图的方式非常相似,因此不需要像上面方法 #3 中的 xml 或属性文件方法那样显式映射文件。
编辑
javadocs for JasperReportsPdfView 提到它使用已弃用的JRExporter API。是否有更好(更新)的 JasperReports 视图可供使用?也许选择JasperReportsMultiFormatView 是一个更好的选择,因为它似乎没有使用JRExporter。