What is the Alternative to the Deprecated MultipartEntity Class in Apache HttpClient?

What are the best alternatives to the deprecated MultipartEntity class in Apache HttpClient for sending multipart requests?

entity.addPart("params", new StringBody("{\"auth\":{\"key\":\"" + authKey + "\"},\"template_id\":\"" + templateId + "\"}"));
entity.addPart("my_file", new FileBody(image));
httppost.setEntity(entity);

Apache HttpClient has deprecated the MultipartEntity class in favor of more modern alternatives. This guide explores the replacement options which offer similar functionality for handling multipart requests effectively.

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.ContentType;

// Create HTTP Post Request
HttpPost httppost = new HttpPost("http://yourapi.com/endpoint");

// Build Multipart Request
MultipartEntityBuilder builder = MultipartEntityBuilder.create();
builder.addTextBody("params", "{\"auth\":{\"key\":\"" + authKey + "\"},\"template_id\":\"" + templateId + "\"}", ContentType.APPLICATION_JSON);
builder.addBinaryBody("my_file", image, ContentType.APPLICATION_OCTET_STREAM, image.getName());

// Set entity to HttpPost
httppost.setEntity(builder.build());

// Execute the request
HttpResponse response = httpClient.execute(httppost);

Causes

• The MultipartEntity class is part of the older HttpClient library and has been deprecated due to issues related to resource leaks and better practices in handling multipart requests.
• Deprecated APIs often suggest using newer classes that improve upon previous implementations, offering better efficiency and easier handling.

Solutions

• Use MultipartEntityBuilder, which is part of the newer Apache HttpComponents libraries. This class provides a fluent API for constructing multipart entities effectively and is the recommended alternative.
• Implement the use of HttpPost with MultipartEntityBuilder as below to achieve the desired functionality.

Mistake: Not properly importing the new MultipartEntityBuilder class.

Solution: Ensure you import MultipartEntityBuilder from the org.apache.http.entity.mime package.

Mistake: Using deprecated methods from MultipartEntity, which could lead to runtime exceptions.

Solution: Always refer to the latest documentation and replace deprecated methods with their recommended alternatives.