arrayutils.java

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    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final long[] array, final long valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(final long[] array, final long valueToFind) {
        return (indexOf(array, valueToFind) != -1);
    }

    // int IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final int[] array, final int valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final int[] array, final int valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final int[] array, final int valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final int[] array, final int valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(final int[] array, final int valueToFind) {
        return (indexOf(array, valueToFind) != -1);
    }

    // short IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final short[] array, final short valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final short[] array, final short valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final short[] array, final short valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final short[] array, final short valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Checks if the value is in the given array.</p>
     *
     * <p>The method returns <code>false</code> if a <code>null</code> array is passed in.</p>
     * 
     * @param array  the array to search through
     * @param valueToFind  the value to find
     * @return <code>true</code> if the array contains the object
     */
    public static boolean contains(final short[] array, final short valueToFind) {
        return (indexOf(array, valueToFind) != -1);
    }

    // byte IndexOf
    //-----------------------------------------------------------------------
    /**
     * <p>Find the index of the given value in the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final byte[] array, final byte valueToFind) {
        return indexOf(array, valueToFind, 0);
    }

    /**
     * <p>Find the index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex is treated as zero. A startIndex larger than the array
     * length will return -1.</p>
     * 
     * @param array  the array to search through for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the index to start searching at
     * @return the index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int indexOf(final byte[] array, final byte valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            startIndex = 0;
        }
        for (int i = startIndex; i < array.length; i++) {
            if (valueToFind == array[i]) {
                return i;
            }
        }
        return -1;
    }

    /**
     * <p>Find the last index of the given value within the array.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     * 
     * @param array  the array to travers backwords looking for the object, may be <code>null</code>
     * @param valueToFind  the object to find
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final byte[] array, final byte valueToFind) {
        return lastIndexOf(array, valueToFind, Integer.MAX_VALUE);
    }

    /**
     * <p>Find the last index of the given value in the array starting at the given index.</p>
     *
     * <p>This method returns <code>-1</code> if <code>null</code> array input.</p>
     *
     * <p>A negative startIndex will return -1. A startIndex larger than the array
     * length will search from the end of the array.</p>
     * 
     * @param array  the array to traverse for looking for the object, may be <code>null</code>
     * @param valueToFind  the value to find
     * @param startIndex  the start index to travers backwards from
     * @return the last index of the value within the array,
     *  <code>-1</code> if not found or <code>null</code> array input
     */
    public static int lastIndexOf(final byte[] array, final byte valueToFind, int startIndex) {
        if (array == null) {
            return -1;
        }
        if (startIndex < 0) {
            return -1;
        } else if (startIndex >= array.length) {
            startIndex = array.length - 1;
        }
        for (int i = startIndex; i >= 0; i--) {
            if (valueToFind == array[i]) {
                return i;
            }
        }