java - write output stream to memory (outputstream to byte array)

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import java.io.DataOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Arrays;

class Program {

    public static void main(String[] args) throws IOException {

        byte[] bytes; 
        try (ByteArrayOutputStream memoryStream = new ByteArrayOutputStream()) {
            try (DataOutputStream outputStream = new DataOutputStream(memoryStream)) {
                outputStream.writeByte(1);
                outputStream.writeShort(2);
                outputStream.writeInt(3);
                outputStream.writeLong(4L);
            }
            bytes = memoryStream.toByteArray();
        }
        System.out.println(Arrays.toString(bytes));  // [1, 0, 2, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 4]
    }
}

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import java.io.OutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

class Program {

    public static void main(String[] args) throws IOException {

        byte[] bytes; 
        try (ByteArrayOutputStream memoryStream = new ByteArrayOutputStream()) {
            OutputStream outputStream = (OutputStream) memoryStream;
            // ...
            bytes = memoryStream.toByteArray();
        }
        // ...
    }
}

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// import java.io.OutputStream;
// import java.io.ByteArrayOutputStream;


byte[] bytes; 
try (ByteArrayOutputStream memoryStream = new ByteArrayOutputStream()) {
    OutputStream outputStream = (OutputStream) memoryStream;
    // ...
    bytes = memoryStream.toByteArray();
}
// ...