What is StringUtils.lastOrdinalIndexOf() in Java?

How to import `StringUtils`

The definition of StringUtils is found in the Apache Commons Lang package. We can add this 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, see the Maven Repository.

You can import the StringUtils class as follows:

import org.apache.commons.lang3.StringUtils;

Syntax

public static int lastOrdinalIndexOf(final CharSequence str, final CharSequence searchStr, final int ordinal)

Parameters

str: This is the text in which we search.
searchStr: This is the sequence to search.
ordinal: This is the nth value.

Return value

This method returns an integer.

<?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

Line 1: We import the StringUtils class.
Line 6: We define the text in which we search as text.
Line 7: We define the search string as searchStr.
Line 8: We define the n value.
Line 10: We obtain the nth last occurrence of the searchStr in text using the lastOrdinalIndexOf() method.
Line 12: We define A new value for n.
Line 13: We obtain the nth last occurrence of the searchStr in text is using thelastOrdinalIndexOf() method. As there is no 5th last occurrence of searchStr in text, the method returns -1.