Java Byte Array Create toBytes(String str, byte[] bytes, int index)

Description

Convert string to bytes and store them in the array starting at the given index.

License

Apache License

Parameter

Parameter	Description
str	a parameter
bytes	a parameter
index	a parameter

Return

the ending index, exclusive.

Declaration

public static int toBytes(String str, byte[] bytes, int index) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

public class Main {
    /**/*from ww  w  . j a v  a  2  s.co m*/
     * Convert int to bytes and store them in the array starting at the given index.
     * 
     * @param val
     * @param bytes
     * @param index
     * @return the ending index, exclusive.
     */
    public static int toBytes(int val, byte[] bytes, int index) {
        int typeBytes = Integer.SIZE / Byte.SIZE;
        checkBounds(bytes, index, typeBytes);
        for (int i = 0; i < typeBytes; i++) {
            int shiftBits = Byte.SIZE * (typeBytes - i - 1);
            byte b = (byte) (val >> shiftBits);
            bytes[index++] = b;
        }
        return index;
    }

    /**
     * Convert long to bytes and store them in the array starting at the given index.
     * @param val
     * @param bytes
     * @param index
     * @return the ending index, exclusive.
     */
    public static int toBytes(long val, byte[] bytes, int index) {
        int typeBytes = Long.SIZE / Byte.SIZE;
        checkBounds(bytes, index, typeBytes);
        for (int i = 0; i < typeBytes; i++) {
            int shiftBits = Byte.SIZE * (typeBytes - i - 1);
            byte b = (byte) (val >> shiftBits);
            bytes[index++] = b;
        }
        return index;
    }

    /**
     * Convert string to bytes and store them in the array starting at the given index.
     * 
     * @param str
     * @param bytes
     * @param index
     * @return the ending index, exclusive.
     */
    public static int toBytes(String str, byte[] bytes, int index) {
        int typeBytes = Character.SIZE / Byte.SIZE;
        checkBounds(bytes, index, typeBytes * str.length());
        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);
            for (int j = typeBytes - 1; j >= 0; j--) {
                int shiftBits = Byte.SIZE * j;
                byte b = (byte) (c >> shiftBits);
                bytes[index++] = b;
            }
        }
        return index;
    }

    /**
     * Utility method used to bounds check the byte array
      * and requested offset & length values.
      * 
     * @param bytes
     * @param offset
     * @param length
     */
    public static void checkBounds(byte[] bytes, int offset, int length) {
        if (length < 0)
            throw new IndexOutOfBoundsException("Index out of range: " + length);
        if (offset < 0)
            throw new IndexOutOfBoundsException("Index out of range: " + offset);
        if (offset > bytes.length - length)
            throw new IndexOutOfBoundsException("Index out of range: " + (offset + length));
    }
}

Related

1. toBytes(String hexString)
2. toBytes(String hexString)
3. toBytes(String name)
4. toBytes(String s)
5. toBytes(String s, int len, byte pad)
6. toBytes4(int n)
7. toBytes4HexString(String str, char... separateds)
8. toBytesBE(long v)
9. toBytesBigEndian(long value, int sizeInByte)