Java 8 – How to remove leading and trailing whitespaces in a String ?

In this article, we will understand with a Java program on how to remove leading and trailing whitespaces from String using Java 1.8 version

Already in one of the previous article, we discussed how to remove leading and trailing whitespaces from String using earlier versions of Java like 5 or 7, etc.

Remove Leading/Trailing whitespaces from String:

  • trim() method of String
    • Removes leading and trailing whitespaces if any from invoking String
    • If the invoking string is null, then java.lang.NullPointerException is thrown

RemoveLeadingAndTrailingWhitespacesFromString.java

package in.bench.resources.java8.string.methods;

import java.util.stream.Stream;

public class RemoveLeadingAndTrailingWhitespacesFromString {

	public static void main(String[] args) {

		// 1. string
		String url = "     BenchResourcesNet     ";


		// 1.1 Trim invoking String
		String trimmedUrl = Stream.of(url).map(String::trim).findFirst().get();
		System.out.println("1. Trimmed 1st String is :- " + trimmedUrl);


		// 2. Empty string
		String str1 = "";


		// 2.1 Trim invoking String
		String trimmedStr1 = Stream.of(str1).map(String::trim).findFirst().get();
		System.out.println("\n2. Trimmed empty String is :- " + trimmedStr1 + "\n\n");


		// 3. null string
		String str2 = null;


		// 3.1 Trim invoking String
		String trimmedStr2 = Stream.of(str2).map(String::trim).findFirst().get();
		System.out.println("\n3. Trimmed null String is :- " + trimmedStr2);
	}
}

Output:

1. Trimmed 1st String is :- BenchResourcesNet

2. Trimmed empty String is :- 


Exception in thread "main" java.lang.NullPointerException
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.Streams$StreamBuilderImpl.tryAdvance(Streams.java:397)
	at java.base/java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:129)
	at java.base/java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:527)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:513)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.FindOps$FindOp.evaluateSequential(FindOps.java:150)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.findFirst(ReferencePipeline.java:647)
	at in.bench.resources.java8.string.methods.RemoveLeadingAndTrailingWhitespacesFromString
.main(RemoveLeadingAndTrailingWhitespacesFromString.java:32)

Related Articles:

References:

Happy Coding !!
Happy Learning !!

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