package com.yangfei.servlet;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

/**
 * @author 杨飞
 * @time 2018.9.11
 * @describe 文件上传
 */
public class FileUploadServlet extends HttpServlet {

    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


        try {
            //接收上传文件

            //1、创建磁盘文件项工厂
            DiskFileItemFactory factory = new DiskFileItemFactory();
            //2、创建文件上传的核心类
            ServletFileUpload upload = new ServletFileUpload(factory);
            //3、解析request---获得文件项集合
            List<FileItem> parseRequest = upload.parseRequest(request);
            //4、遍历文件项集合
            for(FileItem item : parseRequest){
                //5、判断普通表单项/文件上传项
                boolean formField = item.isFormField();//是否是一个普通表单项
                if(formField){
                    //普通表单项
                    String fieldName = item.getFieldName();
                    String fieldValue = item.getString();
                    System.out.println(fieldName+":"+fieldValue);
                }else{
                    //文件上传项
                    //获得上传文件的名称
                    String fileName = item.getName();
                    //获得上传文件的内容
                    InputStream in = item.getInputStream();
                    //将in中的数据拷贝服务器上
                    String path = this.getServletContext().getRealPath("upload");
                    OutputStream out = new FileOutputStream(path+"/"+fileName);
                    int len = 0;
                    byte[] buffer = new byte[1024];
                    while((len=in.read(buffer))>0){
                        out.write(buffer, 0, len);
                    }

                    in.close();
                    out.close();
                }
            }
        } catch (FileUploadException e) {
            e.printStackTrace();
        }
    }
    @Override
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
}