Checks If a String is Not Empty and Not Null in Java

In this post, we demonstrate how to check if a String is not empty and not null in Java with an example.

Checks If a String is Not Empty and Not Null in Java

package net.javaguides.corejava.string; public class StringNotNullAndNotEmpty { public static void main(String[] args) { System.out.println(isNotEmpty(null)); System.out.println(isNotEmpty("")); System.out.println(isNotEmpty("sourcecodeexamples")); } /**  * <p>  * Checks if a CharSequence is empty ("") or null.  * </p>  *   * @param cs  * the CharSequence to check, may be null  * @return {@code true} if the CharSequence is empty or null  * @since 3.0 Changed signature from isEmpty(String) to  * isEmpty(CharSequence)  */ public static boolean isEmpty(final CharSequence cs) { return cs == null || cs.length() == 0; } /**  * <p>  * Checks if a CharSequence is not empty ("") and not null.  * </p>  *   * @param cs  * the CharSequence to check, may be null  * @return {@code true} if the CharSequence is not empty and not null  * @since 3.0 Changed signature from isNotEmpty(String) to  * isNotEmpty(CharSequence)  */ public static boolean isNotEmpty(final CharSequence cs) { return !isEmpty(cs); } }
Output:
false false true

Reference


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