模拟服务器

简介

此demo主要用来模拟ios、Android等开发请求数据服务器返回数据；功能包过一般get、post请求及接受参数；还有文件上传处理，文件下载。

tomcat-8.0.48

http://ot9nmrjuv.bkt.clouddn.com/apache-tomcat-8.0.48-windows-x64.zip

WebDemo.rar

http://ot9nmrjuv.bkt.clouddn.com/WebDemo.rar

结构

BaseServlet.class

import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;

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

import com.google.gson.Gson;
import com.util.CloseIOUtils;
import com.util.LogUtils;
import com.util.StringUtils;

/**
 * 基类 2018年5月4日10:22:21
 * 
 * @author Administrator
 *
 */
public abstract class BaseServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doPost(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {

        response.setContentType("text/html; charset=UTF-8");

        doPost(request, response, setOutObject(), setParams());

    }

    /**
     * 设置参数
     * 
     * @return
     */

    public abstract String[] setParams();

    /**
     * 设置输出对象
     * 
     * @return
     */
    public abstract Object setOutObject();

    public void doPost(HttpServletRequest request, HttpServletResponse response, Object result, String... params) {

        HashMap<String, String> map = new HashMap<>();
        if (params != null) {
            System.out.println("==========================================请求数据====================================");
            for (String key : params) {
                System.out.println(StringUtils.addString("key: ", key, "  value: ",
                        StringUtils.getString(request.getParameter(key))));
                map.put(key, StringUtils.getString(request.getParameter(key)));
            }
            System.out.println("==========================================请求数据====================================");
        }

        PrintWriter out = null;
        String jsonValue = "";
        try {
            out = response.getWriter();
            jsonValue = new Gson().toJson(result);
            out.println(jsonValue);
            System.out.println("==========================================返回数据====================================");
            System.out.println(StringUtils.getString(jsonValue));
            System.out.println("==========================================返回数据====================================");
        } catch (Exception e) {
            System.out.println("\n\n==========================================发生异常====================================");
            e.printStackTrace();
            out.println(jsonValue);
            LogUtils.e(jsonValue);
            System.out.println("\n\n==========================================发生异常====================================");
        }
        CloseIOUtils.clean(out);

    }

}

该基类主要省略一般servlet步骤，并记录过程。

CommonServlet.class

import java.util.ArrayList;
import java.util.Random;

import javax.servlet.annotation.WebServlet;

import com.bean.StudentBean;

@WebServlet("/test")
public class CommonServlet extends BaseServlet {

    private static final long serialVersionUID = 1L;

    @Override
    public String[] setParams() {

        return new String[] { "mac", "loginPwd", "newPwd", "loginName" };
    }

    @Override
    public Object setOutObject() {

        int size = new Random().nextInt(50);
        ArrayList<StudentBean> list = new ArrayList<>();
        for (int i = 0; i < size; i++) {
            list.add(new StudentBean("Jack", "T", "22", "好好学习,天天向上...."));
        }
        return list;
    }

}

设置请求参数

{ “mac”, “loginPwd”, “newPwd”, “loginName” }

设置返回数据

list.add(new StudentBean(“Jack”, “T”, “22”, “好好学习,天天向上….”));

UploadServlet.class

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
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.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import com.util.FileUtils;
import com.util.StringUtils;

@WebServlet("/uploadServlet")
public class UploadServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;
    // 上传目录
    private static final String UPLOAD_DIRECTORY = "upload";
    // 设置内存临界值 - 超过后将产生临时文件并存储于临时目录中
    private static final int MEMORY_THRESHOLD = 1024 * 1024 * 3; // 3MB
    // 设置最大文件上传值
    private static final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB
    // 设置最大请求值 (包含文件和表单数据)
    private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB

    /**
     * 上传数据及保存文件
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        String desc = request.getParameter("desc");
        System.out.println("desc:" + desc);

        // 检测是否为多媒体上传
        if (ServletFileUpload.isMultipartContent(request)) {
            // 配置上传参数
            DiskFileItemFactory factory = new DiskFileItemFactory();
            // 设置内存临界值 - 超过后将产生临时文件并存储于临时目录中
            factory.setSizeThreshold(MEMORY_THRESHOLD);
            // 设置临时存储目录
            factory.setRepository(new File(System.getProperty("java.io.tmpdir")));
            ServletFileUpload upload = new ServletFileUpload(factory);
            // 设置最大文件上传值
            upload.setFileSizeMax(MAX_FILE_SIZE);
            // 设置最大请求值 (包含文件和表单数据)
            upload.setSizeMax(MAX_REQUEST_SIZE);
            // 中文处理
            upload.setHeaderEncoding("UTF-8");
            // 构造临时路径来存储上传的文件
            // 这个路径相对当前应用的目录
            String uploadPath = request.getServletContext().getRealPath("./") + File.separator + UPLOAD_DIRECTORY;
            // 如果目录不存在则创建
            File uploadDir = new File(uploadPath);
            if (!uploadDir.exists()) {
                uploadDir.mkdir();
            }

            try {
                // 解析请求的内容提取文件数据
                List<FileItem> formItems = upload.parseRequest(request);

                if (formItems != null && formItems.size() > 0) {
                    // 迭代表单数据
                    for (FileItem item : formItems) {
                        // 处理不在表单中的字段
                        if (!item.isFormField()) {
                            String fileName = new File(item.getName()).getName();
                            String filePath = uploadPath + File.separator + fileName;
                            File storeFile = new File(filePath);
                            // 在控制台输出文件的上传路径
                            System.out.println(filePath);
                            // 保存文件到硬盘
                            item.write(storeFile);
                            request.setAttribute("message", "文件上传成功!");
                            request.setAttribute("path", filePath);
                        }
                    }
                }
            } catch (Exception ex) {
                request.setAttribute("message", "错误信息: " + ex.getMessage());
                request.setAttribute("path", uploadPath);
            }
        }

        // 跳转到 message.jsp
        request.getServletContext().getRequestDispatcher("/message.jsp").forward(request, response);
    }

}

upload.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>文件上传</title>
</head>
<body>
    <form method="post" action="uploadServlet" enctype="multipart/form-data">

        选择一个文件: <input type="file" name="uploadFile" /> <br/> <br/>

         <input type="submit" value="上传" />
    </form>
</body>
</html>

上传页面

http://localhost:8080/WebDemo/upload.jsp

处理上传页面逻辑，即上传文件api;可用于多文件上传，同时传递参数。

http://localhost:8080/WebDemo/uploadServlet