Java judges whether the string is null, and java judges the string

Java judges whether the string is null, and java judges the string
The following are three methods for Java to determine whether a string is null.
Method 1: The method that most people use is intuitive, convenient, but inefficient.
Method 2: Compare the string length with high efficiency. It is the best method I know.

Method 3: the method provided by Java SE 6.0 is almost the same as method 2. For compatibility reasons, method 2 is recommended.

1: if (s = null | s. equals (""); 2: if (s = null | s. length () <= 0); 3: if (s = null | s. isEmpty ());

Java checks whether the string is null.

The following are three methods for Java to determine whether a string is null.

Method 1: The method that most people use is intuitive, convenient, but inefficient.
1: if (s = null | s. equals (""));
Method 2: Compare the string length with high efficiency. It is the best method I know.
2: if (s = null | s. length () <= 0 );
Method 3: the method provided by Java SE 6.0 is almost the same as method 2. However, for compatibility considerations, we recommend that you use this method.
3: if (s = null | s. isEmpty ());

Java checks whether the string is null.

The following are three methods for Java to determine whether a string is null.

Method 1: The method that most people use is intuitive, convenient, but inefficient.
1: if (s = null | s. equals (""));
Method 2: Compare the string length with high efficiency. It is the best method I know.
2: if (s = null | s. length () <= 0 );
Method 3: the method provided by Java SE 6.0 is almost the same as method 2. However, for compatibility considerations, we recommend that you use this method.
3: if (s = null | s. isEmpty ());