In Java, when writing to a file with DataOutputStream, how do I define the Endian of the data being written?

Question

I'm using DataOutputStream to write to a file, however I want to change the endian of the data.

This is how i'm writing the byte data to the file (it outputs in Little endian by default)

public void generateBinObjFile(String outputFile)
    try {
        // Create file

        DataOutputStream stream = new DataOutputStream(
                new FileOutputStream(outputFile));

        stream.writeShort(this.quantize(this.xComponents.get(index), //<-- Short is written in little Endian
                    this.min_x, this.max_x) - 32768);

        } // catch statements here

Is there a way i can define the Endian of how byte data is written in Java?

Answer 1

You can not do this with DataOutputStream, which always uses big endian.

You can use a ByteBuffer on which you can call order() to influence how it reads and writes data.

You can use the ByteBuffer either to prepare a byte[] that you'll write with a classical OutputStream later on or go entirely to NIO and use any WritableByteChannel for the writing

Answer 2

You can use: com.google.common.io.LittleEndianDataOutputStream from

https://google.github.io/guava/releases/17.0/api/docs/com/google/common/io/LittleEndianDataOutputStream.html or copy this class: http://www.cafeaulait.org/books/javaio/ioexamples/07/LittleEndianOutputStream.java