curl4j

A simple cURL-like Java HTTP client.

Features

• Fluent API for building HTTP requests (GET, POST, PUT, DELETE, HEAD, OPTIONS, CONNECT, TRACE)
• Support for query parameters, headers, body (String or stream), compression, SSL configuration, proxies, and timeouts
• Automatic in-memory or on-disk caching of request/response bodies
• Synchronous and asynchronous (callback) execution
• Minimal dependencies (only Apache Commons IO)

Installation

Maven

Add the dependency to your pom.xml (replace x.y.z with the latest version):

<dependency>
  <groupId>org.codelibs</groupId>
  <artifactId>curl4j</artifactId>
  <version>x.y.z</version>
</dependency>

See Maven Central for available versions.

Gradle

implementation 'org.codelibs:curl4j:x.y.z'

Quick Start

Synchronous request

import org.codelibs.curl.Curl;
import org.codelibs.curl.CurlResponse;

try (CurlResponse response = Curl.get("https://example.com")
                                .param("q", "curl4j")
                                .header("Accept", "application/json")
                                .execute()) {
    System.out.println("Status: " + response.getHttpStatusCode());
    System.out.println(response.getContentAsString());
}

Asynchronous request

import org.codelibs.curl.Curl;

Curl.post("https://api.example.com/items")
    .body("{\"name\":\"item1\"}")
    .header("Content-Type", "application/json")
    .execute(
        response -> System.out.println("Async status: " + response.getHttpStatusCode()),
        error -> error.printStackTrace());

API Overview

• org.codelibs.curl.Curl: entry point for HTTP methods (GET, POST, PUT, DELETE, HEAD, OPTIONS, CONNECT, TRACE).
• org.codelibs.curl.CurlRequest: builder for HTTP requests.
• org.codelibs.curl.CurlResponse: wrapper for HTTP responses.
• org.codelibs.curl.CurlException: unchecked exception for errors.
• org.codelibs.curl.io.ContentCache and ContentOutputStream: internal utilities for streaming and caching.

Refer to the Javadoc for full API details.

Building and Testing

git clone https://github.com/codelibs/curl4j.git
cd curl4j
mvn clean test

License

This project is licensed under the Apache License 2.0. See LICENSE for details.