net.abc.tool.util.base.ObjectUtils Maven / Gradle / Ivy

Go to download
package net.abc.tool.util.base;

import java.lang.reflect.Array;
import java.util.Collection;
import java.util.Map;
import java.util.Optional;

/**
 * @author: zhangwei
 * @date: 23:54/2018-11-29
 */
public abstract class ObjectUtils {

    public static boolean isArray(Object obj) {
        return (obj != null && obj.getClass().isArray());
    }

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

    public static boolean isEmpty(Object obj) {
        if (obj == null) {
            return true;
        }

        if (obj instanceof Optional) {
            return !((Optional) obj).isPresent();
        }
        if (obj instanceof CharSequence) {
            return ((CharSequence) obj).length() == 0;
        }
        if (obj.getClass().isArray()) {
            return Array.getLength(obj) == 0;
        }
        if (obj instanceof Collection) {
            return ((Collection) obj).isEmpty();
        }
        if (obj instanceof Map) {
            return ((Map) obj).isEmpty();
        }
        // else
        return false;
    }

    public static  A[] addObjectToArray(A[] array, O obj) {
        Class compType = Object.class;
        if (array != null) {
            compType = array.getClass().getComponentType();
        }
        else if (obj != null) {
            compType = obj.getClass();
        }
        int newArrLength = (array != null ? array.length + 1 : 1);
        @SuppressWarnings("unchecked")
        A[] newArr = (A[]) Array.newInstance(compType, newArrLength);
        if (array != null) {
            System.arraycopy(array, 0, newArr, 0, array.length);
        }
        newArr[newArr.length - 1] = obj;
        return newArr;
    }

    public static  T checkNotNull(T arg, String text) {
        if (arg == null) {
            throw new NullPointerException(text);
        } else {
            return arg;
        }
    }
}