引入的包:

import java.io.File;
import java.util.Iterator;
import java.util.UUID;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.io.FileUtils;
import org.apache.struts2.ServletActionContext;

import com.gzzs.util.service.HandlerPath;
import com.opensymphony.xwork2.ActionSupport;

html:

<div style="margin-top: 10px; margin-left: 180px">
	<input id="specialrecommendfile" type="file" size="30"
	name="file">
	<button type="button" onclick="UploadSpecialRecommendPic()"
	class="btn btn-warning btn-lg">上传</button>
	<input type=hidden class="span5" id="specialRecommendPic"
	name="riIndexPic">
</div>

function UploadSpecialRecommendPic() {
	$.ajaxFileUpload({
		url : '/GZZSServer/s_util/uploadSpecialRecommendPic.action',
		secureuri : false,
		fileElementId : 'specialrecommendfile',
		dataType : 'json',
		success : function(d, status) {
			var data = http://www.mamicode.com/eval('(' + d + ')');>
action:
public String uploadSpecialRecommendPic() {
		try {
			String path;
			path = "C://";
			FileUtils.copyFile(file, new File(path));
			result = "{flag:\"1\",msg:\"操作成功\",path:\""
					+ HandlerPath.getHostSimulateAuthorLogoPath()
					+ fileFileName + "\",picName:\"" + fileFileName + "\"}";
			return SUCCESS;
		} catch (Exception e) {
			e.printStackTrace();
			result = "{flag:\"0\",msg:\"操作失败\"}";
			return SUCCESS;
		}
}

实例图片:

bootstrap 图片上传实例