How to use StringUtils function for string operations in Java

String operations are very important in Java. We often need to perform various operations such as splicing, cutting, and replacing strings. If you can use professional string manipulation tools, you can implement these operations more efficiently.

One of the more commonly used tools is the StringUtils function library of Apache Commons Lang. The StringUtils function library provides a large number of string manipulation methods, which can greatly simplify the work of developers.

Let’s introduce how to use the StringUtils function to perform string operations in Java.

1. Determining whether a string is empty or null

Determining whether a string is empty or null is a basic operation in Java, and the StringUtils function library can easily implement this function. The following is a method to use StringUtils to determine whether a string is empty or null:

StringUtils.isBlank(str)

This method will determine whether the parameter str is empty or null. If it is empty or null, it returns true, otherwise it returns false. It should be noted that this method can not only determine whether it is empty or null, but also determine whether the string only contains spaces.

In addition to the isBlank() method, the StringUtils function library also provides isNotEmpty() and isNotBlank() methods to determine whether the string is not empty or null.

2. String concatenation

When concatenating strings in Java, we usually use the plus sign ( ) operator. Although this approach is simple, it is very efficient. Low. The StringUtils function library provides many efficient string splicing methods, as follows:

StringUtils.join(objs, separator)

This method can separate the elements in the objs array using the characters specified by the separator. separated and then concatenated into a string. It should be noted that objs can be an array of any type, and separator can be an object of any type.

In addition, the StringUtils function library also provides many other string splicing methods, such as joinWith() and join(), etc.

3. String replacement

When string replacement is performed in Java, the replace() method in String is usually used, which is less efficient. The StringUtils function library provides many efficient string replacement methods, as follows:

StringUtils.replace(str, search, replace)

This method replaces the search part of the string str with Partial replacement returns a new string. It should be noted that both search and replace can be objects of any type.

In addition, the StringUtils function library also provides string replacement methods such as replaceEach() and replaceChars().

4. String cutting

When you need to cut a string in Java, you usually need to use the substring() method in String. But the StringUtils function library provides a more convenient method.

StringUtils.substring(str, start, end)

This method can return the part of the string str starting from index start and ending at index end-1. It should be noted that both start and end can be negative numbers.

In addition, the StringUtils function library also provides methods such as substringBefore() and substringAfter() to implement more refined string cutting operations.

Summary

The above is an important way to use the StringUtils function to perform string operations in Java. These methods are easy to use and efficient, and can greatly simplify the development work of Java programmers. Therefore, for programs that often need to perform string operations, it is recommended to use the StringUtils function library.

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