Android Array Create nullToEmpty(Integer[] array)

Description

Defensive programming technique to change a null reference to an empty one.

This method returns an empty array for a null input array.

As a memory optimizing technique an empty array passed in will be overridden with the empty public static references in this class.

License

Apache License

Parameter

Parameter	Description
array	the array to check for <code>null</code> or empty

Return

the same array, public static empty array if null or empty input

Declaration

public static Integer[] nullToEmpty(Integer[] array)

Method Source Code

//package com.java2s;
/*//from  ww  w . j a  v a2  s.c om
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    /**
     * An empty immutable <code>Object</code> array.
     */
    public static final Object[] EMPTY_OBJECT_ARRAY = new Object[0];
    /**
     * An empty immutable <code>String</code> array.
     */
    public static final String[] EMPTY_STRING_ARRAY = new String[0];
    /**
     * An empty immutable <code>long</code> array.
     */
    public static final long[] EMPTY_LONG_ARRAY = new long[0];
    /**
     * An empty immutable <code>Long</code> array.
     */
    public static final Long[] EMPTY_LONG_OBJECT_ARRAY = new Long[0];
    /**
     * An empty immutable <code>int</code> array.
     */
    public static final int[] EMPTY_INT_ARRAY = new int[0];
    /**
     * An empty immutable <code>Integer</code> array.
     */
    public static final Integer[] EMPTY_INTEGER_OBJECT_ARRAY = new Integer[0];
    /**
     * An empty immutable <code>short</code> array.
     */
    public static final short[] EMPTY_SHORT_ARRAY = new short[0];
    /**
     * An empty immutable <code>Short</code> array.
     */
    public static final Short[] EMPTY_SHORT_OBJECT_ARRAY = new Short[0];
    /**
     * An empty immutable <code>byte</code> array.
     */
    public static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
    /**
     * An empty immutable <code>Byte</code> array.
     */
    public static final Byte[] EMPTY_BYTE_OBJECT_ARRAY = new Byte[0];
    /**
     * An empty immutable <code>double</code> array.
     */
    public static final double[] EMPTY_DOUBLE_ARRAY = new double[0];
    /**
     * An empty immutable <code>Double</code> array.
     */
    public static final Double[] EMPTY_DOUBLE_OBJECT_ARRAY = new Double[0];
    /**
     * An empty immutable <code>float</code> array.
     */
    public static final float[] EMPTY_FLOAT_ARRAY = new float[0];
    /**
     * An empty immutable <code>Float</code> array.
     */
    public static final Float[] EMPTY_FLOAT_OBJECT_ARRAY = new Float[0];
    /**
     * An empty immutable <code>boolean</code> array.
     */
    public static final boolean[] EMPTY_BOOLEAN_ARRAY = new boolean[0];
    /**
     * An empty immutable <code>Boolean</code> array.
     */
    public static final Boolean[] EMPTY_BOOLEAN_OBJECT_ARRAY = new Boolean[0];
    /**
     * An empty immutable <code>char</code> array.
     */
    public static final char[] EMPTY_CHAR_ARRAY = new char[0];
    /**
     * An empty immutable <code>Character</code> array.
     */
    public static final Character[] EMPTY_CHARACTER_OBJECT_ARRAY = new Character[0];

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Object[] nullToEmpty(Object[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static String[] nullToEmpty(String[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_STRING_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static long[] nullToEmpty(long[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_LONG_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static int[] nullToEmpty(int[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_INT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static short[] nullToEmpty(short[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_SHORT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static char[] nullToEmpty(char[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_CHAR_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static byte[] nullToEmpty(byte[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_BYTE_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static double[] nullToEmpty(double[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_DOUBLE_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static float[] nullToEmpty(float[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_FLOAT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static boolean[] nullToEmpty(boolean[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_BOOLEAN_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Long[] nullToEmpty(Long[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_LONG_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Integer[] nullToEmpty(Integer[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_INTEGER_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Short[] nullToEmpty(Short[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_SHORT_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Character[] nullToEmpty(Character[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_CHARACTER_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Byte[] nullToEmpty(Byte[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_BYTE_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Double[] nullToEmpty(Double[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_DOUBLE_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Float[] nullToEmpty(Float[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_FLOAT_OBJECT_ARRAY;
        }
        return array;
    }

    /**
     * <p>Defensive programming technique to change a <code>null</code>
     * reference to an empty one.</p>
     *
     * <p>This method returns an empty array for a <code>null</code> input array.</p>
     * 
     * <p>As a memory optimizing technique an empty array passed in will be overridden with 
     * the empty <code>public static</code> references in this class.</p>
     *
     * @param array  the array to check for <code>null</code> or empty
     * @return the same array, <code>public static</code> empty array if <code>null</code> or empty input
     * @since 2.5
     */
    public static Boolean[] nullToEmpty(Boolean[] array) {
        if (array == null || array.length == 0) {
            return EMPTY_BOOLEAN_OBJECT_ARRAY;
        }
        return array;
    }
}