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cn.t.util.common.ObjectUtil Maven / Gradle / Ivy

package cn.t.util.common;

import java.util.Arrays;
import java.util.Objects;

public class ObjectUtil {

    private static final int INITIAL_HASH = 7;
    private static final int MULTIPLIER = 31;


    public static boolean isNull(Object obj) {
        return Objects.isNull(obj);
    }

    public static boolean isEmpty(Object[] array) {
        return (array == null || array.length == 0);
    }

    public static boolean isNotNull(Object obj) {
        return !isNull(obj);
    }

    /**
     * Return as hash code for the given object; typically the value of
     * {@code Object#hashCode()}}. If the object is an array,
     * this method will delegate to any of the {@code nullSafeHashCode}
     * methods for arrays in this class. If the object is {@code null},
     * this method returns 0.
     *
     * @param obj xxx
     * @see Object#hashCode()
     * @see #nullSafeHashCode(Object[])
     * @see #nullSafeHashCode(boolean[])
     * @see #nullSafeHashCode(byte[])
     * @see #nullSafeHashCode(char[])
     * @see #nullSafeHashCode(double[])
     * @see #nullSafeHashCode(float[])
     * @see #nullSafeHashCode(int[])
     * @see #nullSafeHashCode(long[])
     * @see #nullSafeHashCode(short[])
     * @return xxx
     */
    public static int nullSafeHashCode(Object obj) {
        if (obj == null) {
            return 0;
        }
        if (obj.getClass().isArray()) {
            if (obj instanceof Object[]) {
                return nullSafeHashCode((Object[]) obj);
            }
            if (obj instanceof boolean[]) {
                return nullSafeHashCode((boolean[]) obj);
            }
            if (obj instanceof byte[]) {
                return nullSafeHashCode((byte[]) obj);
            }
            if (obj instanceof char[]) {
                return nullSafeHashCode((char[]) obj);
            }
            if (obj instanceof double[]) {
                return nullSafeHashCode((double[]) obj);
            }
            if (obj instanceof float[]) {
                return nullSafeHashCode((float[]) obj);
            }
            if (obj instanceof int[]) {
                return nullSafeHashCode((int[]) obj);
            }
            if (obj instanceof long[]) {
                return nullSafeHashCode((long[]) obj);
            }
            if (obj instanceof short[]) {
                return nullSafeHashCode((short[]) obj);
            }
        }
        return obj.hashCode();
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(Object[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (Object element : array) {
            hash = MULTIPLIER * hash + nullSafeHashCode(element);
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(boolean[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (boolean element : array) {
            hash = MULTIPLIER * hash + hashCode(element);
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(byte[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (byte element : array) {
            hash = MULTIPLIER * hash + element;
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(char[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (char element : array) {
            hash = MULTIPLIER * hash + element;
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(double[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (double element : array) {
            hash = MULTIPLIER * hash + hashCode(element);
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(float[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (float element : array) {
            hash = MULTIPLIER * hash + hashCode(element);
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(int[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (int element : array) {
            hash = MULTIPLIER * hash + element;
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(long[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (long element : array) {
            hash = MULTIPLIER * hash + hashCode(element);
        }
        return hash;
    }

    /**
     * Return a hash code based on the contents of the specified array.
     * If {@code array} is {@code null}, this method returns 0.
     * @param array xxx
     * @return xxx
     */
    public static int nullSafeHashCode(short[] array) {
        if (array == null) {
            return 0;
        }
        int hash = INITIAL_HASH;
        for (short element : array) {
            hash = MULTIPLIER * hash + element;
        }
        return hash;
    }

    /**
     * Return the same value as {@link Boolean#hashCode()}}.
     *
     * @param bool xxx
     * @see Boolean#hashCode()
     * @return xxx
     */
    public static int hashCode(boolean bool) {
        return (bool ? 1231 : 1237);
    }

    /**
     * Return the same value as {@link Double#hashCode()}}.
     *
     * @param dbl xxx
     * @see Double#hashCode()
     * @return xxx
     */
    public static int hashCode(double dbl) {
        return hashCode(Double.doubleToLongBits(dbl));
    }

    /**
     * Return the same value as {@link Float#hashCode()}}.
     *
     * @param flt xxx
     * @see Float#hashCode()
     * @return xxx
     */
    public static int hashCode(float flt) {
        return Float.floatToIntBits(flt);
    }

    /**
     * Return the same value as {@link Long#hashCode()}}.
     *
     * @param lng  xxx
     * @see Long#hashCode()
     * @return xxx
     */
    public static int hashCode(long lng) {
        return (int) (lng ^ (lng >>> 32));
    }

    /**
     * Determine if the given objects are equal, returning {@code true} if
     * both are {@code null} or {@code false} if only one is {@code null}.
     * 

Compares arrays with {@code Arrays.equals}, performing an equality * check based on the array elements rather than the array reference. * * @param o1 first Object to compare * @param o2 second Object to compare * @return whether the given objects are equal * @see Object#equals(Object) * @see java.util.Arrays#equals */ public static boolean nullSafeEquals(Object o1, Object o2) { if (o1 == o2) { return true; } if (o1 == null || o2 == null) { return false; } if (o1.equals(o2)) { return true; } if (o1.getClass().isArray() && o2.getClass().isArray()) { return arrayEquals(o1, o2); } return false; } /** * Compare the given arrays with {@code Arrays.equals}, performing an equality * check based on the array elements rather than the array reference. * * @param o1 first array to compare * @param o2 second array to compare * @return whether the given objects are equal * @see #nullSafeEquals(Object, Object) * @see java.util.Arrays#equals */ private static boolean arrayEquals(Object o1, Object o2) { if (o1 instanceof Object[] && o2 instanceof Object[]) { return Arrays.equals((Object[]) o1, (Object[]) o2); } if (o1 instanceof boolean[] && o2 instanceof boolean[]) { return Arrays.equals((boolean[]) o1, (boolean[]) o2); } if (o1 instanceof byte[] && o2 instanceof byte[]) { return Arrays.equals((byte[]) o1, (byte[]) o2); } if (o1 instanceof char[] && o2 instanceof char[]) { return Arrays.equals((char[]) o1, (char[]) o2); } if (o1 instanceof double[] && o2 instanceof double[]) { return Arrays.equals((double[]) o1, (double[]) o2); } if (o1 instanceof float[] && o2 instanceof float[]) { return Arrays.equals((float[]) o1, (float[]) o2); } if (o1 instanceof int[] && o2 instanceof int[]) { return Arrays.equals((int[]) o1, (int[]) o2); } if (o1 instanceof long[] && o2 instanceof long[]) { return Arrays.equals((long[]) o1, (long[]) o2); } if (o1 instanceof short[] && o2 instanceof short[]) { return Arrays.equals((short[]) o1, (short[]) o2); } return false; } }





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