UPLOAD_DIR = System.getProperty("user.dir") + "/upload/";

根据引用中的代码，UPLOAD_DIR = System.getProperty("user.dir") + "/upload/"; 这行代码的功能是获取当前项目的存放路径，并在路径后面加上"/upload/"作为相对路径。所以UPLOAD_DIR的值应该是当前项目存放路径下的upload文件夹的路径。<span class="em">1</span><span class="em">2</span><span class="em">3</span>
#### 引用[.reference_title]
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