How to determine whether an object is empty in java

How to determine whether an object is empty in java:

First, let’s take a look at the determination method of the tool StringUtils:

One is under the org.apache.commons.lang3 package; the other is under the org.springframework.util package.

There is a difference between these two StringUtils tool classes in determining whether an object is empty:

StringUtils.isEmpty(CharSequence cs); 
//org.apache.commons.lang3包下的StringUtils类，判断是否为空的方法参数是字符序列类，也就是String类型

StringUtils.isEmpty(Object str); 
//而org.springframework.util包下的参数是Object类，也就是不仅仅能判断String类型，还能判断其他类型，比如Long等类型。

From the above example, we can see that the second StringUtils class is more practical.

Let’s take a look at the source code of StringUtils.isEmpty(CharSequence cs) of org.apache.commons.lang3:

public static boolean isEmpty(final CharSequence cs) {
        return cs == null || cs.length() == 0;
}

The next step is StringUtils.isEmpty(Object str) of org.springframework.util Source code:

public static boolean isEmpty(Object str) {
        return (str == null || "".equals(str));
}

Basically determine whether the object is empty, StringUtils.isEmpty(Object str) can do this.

For more java knowledge, please pay attention to java basic tutorial.

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