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org.apache.commons.httpclient.methods.multipart 
Class MultipartRequestEntity

java.lang.Object
org.apache.commons.httpclient.methods.multipart.MultipartRequestEntity
All Implemented Interfaces:
RequestEntity

public class MultipartRequestEntity
extends Object
implements RequestEntity
Implements a request entity suitable for an HTTP multipart POST method.

The HTTP multipart POST method is defined in section 3.3 of RFC1867:

The media-type multipart/form-data follows the rules of all multipart MIME data streams as outlined in RFC 1521. The multipart/form-data contains a series of parts. Each part is expected to contain a content-disposition header where the value is "form-data" and a name attribute specifies the field name within the form, e.g., 'content-disposition: form-data; name="xxxxx"', where xxxxx is the field name corresponding to that field. Field names originally in non-ASCII character sets may be encoded using the method outlined in RFC 1522.
This entity is designed to be used in conjunction with the post method to provide multipart posts. Example usage:

  File f = new File("/path/fileToUpload.txt");
  PostMethod filePost = new PostMethod("http://host/some_path");
  Part[] parts = {
      new StringPart("param_name", "value"),
      new FilePart(f.getName(), f)
  };
  filePost.setRequestEntity(
      new MultipartRequestEntity(parts, filePost.getParams())
      );
  HttpClient client = new HttpClient();
  int status = client.executeMethod(filePost);

要引入的Maven：

        <dependency>
            <groupId>org.kie.modules</groupId>
            <artifactId>org-apache-commons-httpclient</artifactId>
            <version>6.2.0.CR1</version>
        </dependency>