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package org.mybatis.generator.internal.util;

/**
 * This class is from javapractices.com:
 * 
 * http://www.javapractices.com/Topic17.cjp
 * 
 * Collected methods which allow easy implementation of equals.
 * 
 * Example use case in a class called Car:
 * 
 *  * public boolean equals(Object that) {
 *     if (this == that)
 *         return true;
 *     if (!(that instanceof Car))
 *         return false;
 *     Car thatCar = (Car) that;
 *     return EqualsUtil.areEqual(this.fName, that.fName)
 *             && EqualsUtil.areEqual(this.fNumDoors, that.fNumDoors)
 *             && EqualsUtil.areEqual(this.fGasMileage, that.fGasMileage)
 *             && EqualsUtil.areEqual(this.fColor, that.fColor)
 *             && Arrays.equals(this.fMaintenanceChecks, that.fMaintenanceChecks); //array!
 * }
 * 
 * 
 * Arrays are not handled by this class. This is because the
 * Arrays.equals methods should be used for array fields.
 */
public final class EqualsUtil {

    static public boolean areEqual(boolean aThis, boolean aThat) {
        return aThis == aThat;
    }

    static public boolean areEqual(char aThis, char aThat) {
        return aThis == aThat;
    }

    static public boolean areEqual(long aThis, long aThat) {
        /*
         * Implementation Note Note that byte, short, and int are handled by
         * this method, through implicit conversion.
         */
        return aThis == aThat;
    }

    static public boolean areEqual(float aThis, float aThat) {
        return Float.floatToIntBits(aThis) == Float.floatToIntBits(aThat);
    }

    static public boolean areEqual(double aThis, double aThat) {
        return Double.doubleToLongBits(aThis) == Double.doubleToLongBits(aThat);
    }

    /**
     * Possibly-null object field.
     *
     * Includes type-safe enumerations and collections, but does not include
     * arrays. See class comment.
     * @param aThis aThis
     * @param aThat aThat
     * @return boolean
     */
    static public boolean areEqual(Object aThis, Object aThat) {
        return aThis == null ? aThat == null : aThis.equals(aThat);
    }
}