页面显示 2进制数据（xml 图片）

最新推荐文章于 2021-06-20 00:31:38 发布

最新推荐文章于 2021-06-20 00:31:38 发布 · 107 阅读

文章标签：

#XML #Workflow #JSP #Struts #Web

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本文介绍了如何使用Struts框架实现工作流的管理功能，包括查看流程定义、显示流程图片及流程定义详情。通过特定的方法调用，实现了从数据库中获取流程图片及定义，并将其展示在前端界面上。

//打开查看流程图片的界面
	public ActionForward viewImage(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		
		WorkflowActionForm waf = (WorkflowActionForm)form;
		Workflow workflow = workflowManager.findWorkflow(waf.getId());
		request.setAttribute("workflow", workflow);
		return mapping.findForward("view_image");
	}
	
	//获取流程图片信息进行显示
	public ActionForward image(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		
		WorkflowActionForm waf = (WorkflowActionForm)form;
		Workflow workflow = workflowManager.findWorkflow(waf.getId());
		
		byte[] processImage = workflow.getProcessImage();
		
		response.setContentType("image/jpeg");
		response.getOutputStream().write(processImage);
		
		return null;
	}
	
	//查看流程定义界面
	public ActionForward viewDef(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {

		WorkflowActionForm waf = (WorkflowActionForm)form;
		Workflow workflow = workflowManager.findWorkflow(waf.getId());
		request.setAttribute("workflow", workflow);
		byte[] processDef = workflow.getProcessDef();
		
		String def = new SAXReader().read(new ByteArrayInputStream(processDef)).asXML();
		
		request.setAttribute("def", def);
		
		return mapping.findForward("view_def");
	}

	public void setWorkflowManager(WorkflowManager workflowManager) {
		this.workflowManager = workflowManager;
	}


		struts-config.xml

		<action 
			path="/workflow"
			type="org.springframework.web.struts.DelegatingActionProxy"
			parameter="method"
			name="workflowForm"
			scope="request"
		>
			<forward name="index" path="/workflow/index.jsp"></forward>
			<forward name="add_success" path="/workflow.do" redirect="true"></forward>
			<forward name="view_image" path="/workflow/view_image.jsp"></forward>
			<forward name="view_def" path="/workflow/view_def.jsp"></forward>
		</action>	

	jsp 

	显示2进制xml 文件 

		<TR>
			<td align="left">
			<!-- 主输入域开始 -->
				<pre><c:out value="${def }" escapeXml="true" /></pre>
			<!-- 主输入域结束 -->
			</td>
		</TR>
	
	显示2进制图片

		<TR>
			<td>
			<!-- 主输入域开始 -->
				<img src="workflow.do?method=image&id=${workflow.id }">
			<!-- 主输入域结束 -->
			</td>
		</TR>