RawHTTP makes it easy to replace the body of a HTTP message, changing the relevant headers as appropriate.

Set body from String

import rawhttp.core.*;
import rawhttp.core.body.*;

RawHttp http = new RawHttp();
RawHttpRequest request = http.parseRequest(
    "POST http://example.com/hello");
RawHttpRequest requestWithBody = request.withBody(
    new StringBody("Hello RawHTTP", "text/plain"));

System.out.println(requestWithBody.eagerly());

Prints:

POST /hello HTTP/1.1
Host: example.com
Content-Type: text/plain
Content-Length: 13

Hello RawHTTP

Set body from File

import rawhttp.core.*;
import rawhttp.core.body.*;

RawHttp http = new RawHttp();
RawHttpRequest request = http.parseRequest(
    "POST http://example.com/hello");
RawHttpRequest requestWithBody = request.withBody(
    new FileBody(new File("hello.request"), "text/plain"));

Set body from byte array

import rawhttp.core.*;
import rawhttp.core.body.*;

byte[] bytes = "Hello RawHTTP".getBytes();

RawHttp http = new RawHttp();
RawHttpRequest request = http.parseRequest(
    "POST http://example.com/hello");
RawHttpRequest requestWithBody = request.withBody(
    new BytesBody(bytes, "text/plain"));

Set body from InputStream (chunked)

import rawhttp.core.*;
import rawhttp.core.body.*;

InputStream stream = new ByteArrayInputStream(
    "Hello RawHTTTP".getBytes());
int chunkSize = 4;

RawHttp http = new RawHttp();
RawHttpRequest request = http.parseRequest(
    "POST http://example.com/hello");
RawHttpRequest requestWithBody = request.withBody(
    new ChunkedBody(stream, "text/plain", chunkSize));

The InputStream is read lazily as the body of the HTTP message is consumed by a reader.

The header Transfer-Encoding: chunked is set, and the body is encoded accordingly.

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