JAVA--将图片转为BASE64编码并返回thymeleaf页面

controller

 1 package cn.lntop.controller.test;
 2 
 3 import java.util.ArrayList;
 4 import java.util.HashMap;
 5 import java.util.List;
 6 import java.util.Map;
 7 
 8 import javax.servlet.http.HttpServletRequest;
 9 
10 import org.apache.commons.lang3.StringUtils;
11 import org.springframework.beans.factory.annotation.Autowired;
12 import org.springframework.beans.factory.annotation.Value;
13 import org.springframework.stereotype.Controller;
14 import org.springframework.ui.ModelMap;
15 import org.springframework.web.bind.annotation.RequestMapping;
16 import org.springframework.web.bind.annotation.RequestMethod;
17 import org.springframework.web.bind.annotation.ResponseBody;
18 
19 import cn.lntop.util.ReturnUtil;
20 import tk.mybatis.mapper.util.StringUtil;
21 
22 @Controller
23 @RequestMapping("/test")
24 public class TestController {
25     
26     /**
27      * 取得电脑信息
28      * @param request
29      * @return
30      */
31     @RequestMapping(value="/test/comInfo", method = {RequestMethod.GET})
32     public ModelMap getTestInfo(HttpServletRequest request) {
33 　　　　　    // 取得URL后的参数
34         String comId = request.getParameter("comId");
35         Map<String, Object> param = new HashMap<String, Object>();
36         param.put("comId", comId)
37         // 查询电脑基本信息步骤--略
38 　　　　　ComInfo com = comService.selectComInfo(param); 
39         try {
40             // 取得图片所在位置
41             String imgPath = this.getClass().getResource("/").getPath() + "/" + com.getImageName();
42             // 将图片转化为base64
43             String base64 = ImgBase64Util.getImgStr(imgPath);
44             // 拼接图片头
45             String head = headFile(imgPath);
46             com.setHeadData(head + base64);
47         } catch (Exception e) {
48             e.printStackTrace();
49         }
50         ModelMap map = new ModelMap();
51         map.put("com", com);
52         return ReturnUtil.Success("操作成功", map, null);
53     }
54 
55     /**
56      * 拼接Base64头信息
57      * @param urlString
58      */
59     public String headFile(String urlString) {
60         String head = "";
61         String type = urlString.substring(urlString.lastIndexOf('.') + 1);
62         if ("png".equals(type)) {
63             head = "data:image/png;base64,";
64         } else if ("jpg".equals(type)) {
65             head = "data:image/jpg;base64,";
66         } else if ("jpeg".equals(type)) {
67             head = "data:image/jpeg;base64,";
68         } else {
69             head = "data:image/jpg;base64,";
70         }
71         return head;
72     }
73     
74 }

Base64工具类

package cn.test.util;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.commons.codec.binary.Base64;


/**
 * 将图片转换为Base64
 * 将base64编码字符串解码成img图片
 *
 */
public class ImgBase64Util {

    /**
     * 将图片转换成Base64编码
     * @param imgFile 待处理图片
     * @return
     */
    public static String getImgStr(String imgFile){
        
        InputStream in = null;
        byte[] data = null;
        //读取图片字节数组
        try 
        {
            in = new FileInputStream(imgFile);        
            data = new byte[in.available()];
            in.read(data);
            in.close();
        } 
        catch (IOException e) 
        {
            e.printStackTrace();
        }
        return new String(Base64.encodeBase64(data));
    }
    
    /**
     * 对字节数组字符串进行Base64解码并生成图片
     * @param imgStr 图片数据
     * @param imgFilePath 保存图片全路径地址
     * @return
     */
    public static boolean generateImage(String imgStr,String imgFilePath){
        //
        if (imgStr == null) //图像数据为空
            return false;
     
        try 
        {
            //Base64解码
            byte[] b = Base64.decodeBase64(imgStr);
            for(int i=0;i<b.length;++i)
            {
                if(b[i]<0)
                {//调整异常数据
                    b[i]+=256;
                }
            }
            //生成jpeg图片

            OutputStream out = new FileOutputStream(imgFilePath);    
            out.write(b);
            out.flush();
            out.close();
            return true;
        } 
        catch (Exception e) 
        {
            return false;
        }
    }
    
    public static void main(String[] args) {
//        String imgFile = "d:\3.jpg";//待处理的图片
//        String imgbese=getImgStr(imgFile);
//        System.out.println(imgbese.length());
//        System.out.println(imgbese);
//        String imgFilePath = "d:\332.jpg";//新生成的图片
//        generateImage(imgbese,imgFilePath);
    }
}

返回thymeleaf格式

package cn.test.util;

import org.apache.commons.lang3.StringUtils;
import org.springframework.ui.ModelMap;

/**
 * JSON统一返回数据格式

 */
public class ReturnUtil {

    public static ModelMap Success(String msg, Object obj, String referer) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作成功" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 1);
        mp.put("state", "success");
        mp.put("msg", msg);
        mp.put("referer", referer);
        mp.put("result", obj);
        return mp;
    }

    public static ModelMap Success(String msg, Object obj) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作成功" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 1);
        mp.put("state", "success");
        mp.put("msg", msg);
        mp.put("referer", null);
        mp.put("result", obj);
        return mp;
    }
    public static ModelMap Success(String msg) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作成功" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 1);
        mp.put("state", "success");
        mp.put("msg", msg);
        mp.put("referer", null);
        mp.put("result", null);
        return mp;
    }

    public static ModelMap Error(String msg, Object obj, String referer) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作失败" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 0);
        mp.put("state", "error");
        mp.put("msg", msg);
        mp.put("referer", referer);
        mp.put("result", obj);
        return mp;
    }

    public static ModelMap Error(String msg, Object obj) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作失败" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 0);
        mp.put("state", "error");
        mp.put("msg", msg);
        mp.put("referer", null);
        mp.put("result", obj);
        return mp;
    }

    public static ModelMap Error(String msg) {
        msg = StringUtils.isEmpty(msg) || StringUtils.isBlank(msg) ? "操作失败" : msg;
        ModelMap mp = new ModelMap();
        mp.put("status", 0);
        mp.put("state", "error");
        mp.put("msg", msg);
        mp.put("referer", null);
        mp.put("result", null);
        return mp;
    }
}

thymeleaf页面

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
    <head>
        <meta charset="utf-8" />
        <title></title>
        <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />
        <meta name="format-detection" content="telephone=no,email=no,adress=no" />
        <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
        <meta name="keywords" content="">
        <meta name="description" content="">
        <meta name="author" content="">
    </head>
    <body class="gray-bg">
        <span>桌面图片</span>
        <img th:src="${result.com.headData}" class="header-img"/>
    </body>
</html>