阿里云OSS图片上传（java web直传）

本文主要是介绍阿里云OSS图片上传（java web直传），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

最近使用到阿里云的OSS做图片上传，特别记录操作流程。

本demo是最原汁原味的oss图片上传，基本没有经过加工，最容易读懂和理解。

一创建bucket和配置跨域

创建bucket步骤:

略。（为了访问方便，建议读写权限设置为公共读）

配置跨域：

权限管理>>跨域设置，如果不设置话的，上传文件时，浏览器会提示禁止跨域403

二服务端签名（java版）

（1）maven导包

<dependency><groupId>com.aliyun.oss</groupId><artifactId>aliyun-sdk-oss</artifactId><version>3.11.1</version></dependency><dependency>  <groupId>net.sf.json-lib</groupId>  <artifactId>json-lib</artifactId>  <version>2.2.3</version>  <classifier>jdk15</classifier><!-- 指定jdk版本 -->  </dependency>

（2）填写accessId,accessKey,endPoint(demo写的杭州),bucket。

package com.durian.amanager.servlet;import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;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.lang3.StringUtils;import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.common.utils.BinaryUtil;
import com.aliyun.oss.model.MatchMode;
import com.aliyun.oss.model.PolicyConditions;import net.sf.json.JSONObject;//获取阿里云oss policy
@WebServlet(urlPatterns = "/aliyunoss_getpolicy")
public class AliyunOssServlet extends HttpServlet {/*** */private static final long serialVersionUID = 4108505220500631L;protected void service(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String dir=request.getParameter("dir");// 用户上传文件时指定的前缀。if(StringUtils.isEmpty(dir)){dir="";}else{dir=dir+"/";}String accessId = "<yourAccessKeyId>"; // 请填写您的AccessKeyId。String accessKey = "<yourAccessKeySecret>"; // 请填写您的AccessKeySecret。String endpoint = "oss-cn-hangzhou.aliyuncs.com"; // 请填写您的 endpoint。String bucket = "bucket-name"; // 请填写您的 bucketname 。String host = "https://" + bucket + "." + endpoint; // host的格式为// bucketname.endpoint// callbackUrl为 上传回调服务器的URL，请将下面的IP和Port配置为您自己的真实信息。String callbackUrl = "";//String format = new SimpleDateFormat("yyyy-MM-dd").format(new Date());// 创建OSSClient实例。OSS ossClient = new OSSClientBuilder().build(endpoint, accessId, accessKey);try {long expireTime = 300;long expireEndTime = System.currentTimeMillis() + expireTime * 1000;Date expiration = new Date(expireEndTime);// PostObject请求最大可支持的文件大小为5// GB，即CONTENT_LENGTH_RANGE为5*1024*1024*1024。PolicyConditions policyConds = new PolicyConditions();policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, 1048576000);policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);String postPolicy = ossClient.generatePostPolicy(expiration, policyConds);byte[] binaryData = postPolicy.getBytes("utf-8");String encodedPolicy = BinaryUtil.toBase64String(binaryData);String postSignature = ossClient.calculatePostSignature(postPolicy);Map<String, String> respMap = new LinkedHashMap<String, String>();respMap.put("accessid", accessId);respMap.put("policy", encodedPolicy);respMap.put("signature", postSignature);respMap.put("dir", dir);respMap.put("host", host);respMap.put("expire", String.valueOf(expireEndTime / 1000));// respMap.put("expire", formatISO8601Date(expiration));JSONObject jasonCallback = new JSONObject();jasonCallback.put("callbackUrl", callbackUrl);jasonCallback.put("callbackBody","filename=${object}&size=${size}&mimeType=${mimeType}&height=${imageInfo.height}&width=${imageInfo.width}");jasonCallback.put("callbackBodyType", "application/x-www-form-urlencoded");String base64CallbackBody = BinaryUtil.toBase64String(jasonCallback.toString().getBytes());respMap.put("callback", base64CallbackBody);JSONObject ja1 = JSONObject.fromObject(respMap);// System.out.println(ja1.toString());response.setHeader("Access-Control-Allow-Origin", "*");response.setHeader("Access-Control-Allow-Methods", "GET, POST");response(request, response, ja1.toString());} catch (Exception e) {// Assert.fail(e.getMessage());System.out.println(e.getMessage());} finally {ossClient.shutdown();}}/*** 回传参数* * @param resp*            回传类* @param data*            回传数据* @throws IOException*/public static void response(HttpServletRequest request, HttpServletResponse response, String data) {try {response.setCharacterEncoding("utf-8");response.setContentType("text/html");PrintWriter out = response.getWriter();out.print(data);out.flush();out.close();} catch (Exception e) {e.printStackTrace();}}}