accessoryresult.java

本源码为教学管理信息系统

package com.wygl.fjgl.action;

import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Connection;

import javax.servlet.http.HttpServletResponse;

import com.opensymphony.webwork.ServletActionContext;
import com.opensymphony.xwork.ActionInvocation;
import com.opensymphony.xwork.Result;
import com.opensymphony.xwork.util.OgnlValueStack;
/**
 * @author Administrator
 * 附件文件下载结果
 */
public class AccessoryResult implements Result {
	/**
	 * 文件输入流
	 */
	private InputStream input;
	
	/**
	 * 文件名称
	 */
	private String fileName;
	/**
	 * 数据源
	 */
	private Connection con;
	/* 
	 * @see com.opensymphony.xwork.Result#execute(com.opensymphony.xwork.ActionInvocation)
	 */
	public void execute(ActionInvocation arg0) throws Exception {
		try {
			OgnlValueStack stack = (OgnlValueStack) ServletActionContext.getRequest().getAttribute("webwork.valueStack");		
			input = (InputStream) stack.findValue("input");
			fileName = (String) stack.findValue("fileName");
			con = (Connection) stack.findValue("con");
			
			if (input == null) {
				throw new NullPointerException("No input found");
			}
			
			if (fileName == null) {
				throw new NullPointerException("No fileName found");
			}
			
			if (con == null) {
				throw new NullPointerException("No con found");
			}
			
			HttpServletResponse response = ServletActionContext.getResponse();
			response.reset();
			response.setContentType("application/octet-stream");
			response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
			OutputStream out = response.getOutputStream();
			byte[] buffer = new byte[102400];
			int bytes = 0;
			while ((bytes = input.read(buffer)) != -1) {
				out.write(buffer, 0, bytes);
			}
			input.close();
			out.close();
			if(con != null){
				con.close();
			}		
		} catch (Exception e) {			
		}
	}
}