What is the StringUtils.rightPad method in Java?
In Java, rightPad() is a StringUtils, which is used to right pad spaces to the given string. There are three variations of the method:
rightPad(final String str, final int size)rightPad(final String str, final int size, final char padChar)rightPad(final String str, final int size, String padStr)
Import StringUtils
The definition of StringUtils can be found in the Apache Commons Lang package, which we can add to the Maven project by adding the following dependency to the pom.xml file:
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.12.0</version>
</dependency>
Note: For other versions of the commons-lang package, refer to the Maven Repository.
We can import the StringUtils class as follows:
import org.apache.commons.lang3.StringUtils;
The rightPad(final String str, final int size) method
This method is used to pad spaces to the right side of the string. The number of spaces padded is equal to the difference of the specified size and the length of the given string.
If the size parameter is negative or less than the length of the given string, it returns the given string without padding.
public static String rightPad(final String str, final int size)
Parameters
final String str: The string to be padded.final int size: The final length of the string after padding.
Return value
This method returns a new right padded string.
The rightPad(final String str, final int size, final char padChar) method
This method is used to pad the given character to the right side of the string. The number of characters padded is equal to the difference of the specified size and the length of the given string.
If the size parameter is negative or less than the length of the given string, it returns the given string without padding.
public static String rightPad(final String str, final int size, final char padChar)
Parameters
final String str: The string to be padded.final int size: The final length of the string after padding.final char padChar: The character to pad.
Return value
This method returns a right padded string.
The rightPad(final String str, final int size, String padStr) method
This method is used to pad the given string, padStr, to the right side of the string. The number of pad strings, padStr, padded is equal to the difference of the specified size and the length of the given string.
If the size parameter is negative or less than the length of the given string, it returns the given string without any padding.
rightPad(final String str, final int size, String padStr)
Parameters
final String str: The string to be padded.final int size: The final length of the string after padding.String padStr: The string to pad.
Return value
This method returns a new right padded string.
Examples
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>test</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.12.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.1</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<transformer
implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>Main</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>Explanation
The maven dependency for StringUtils is included in the pom.xml file:
Main.java
- Line 1: We import the
StringUtilsclass. - Line 6: We define a
Stringcalledtext. - Line 7: We define the size for the padding,
numPadding. - Lines 8–10: - We invoke the
rightPad()method passingtextandnumPaddingas parameters. We store the output inpaddedText. The output is the spaces padded to the right oftext. We printpaddedText. - Line 12: We define the padding character,
paddingChar. - Lines 13–15: We invoke the
rightPad()method passingtext,numPaddingandpaddingCharas parameters. We store the output inpaddedText. The output is thepaddingCharpadded to the right oftext. We printpaddedText.