The java.lang.Character.isLowSurrogate(char ch) is an inbuilt method in java which determines if the given char value is a Unicode low-surrogate code unit (also known as trailing-surrogate code unit). Such values do not represent characters by themselves but are used in the representation of supplementary characters in the UTF-16 encoding.
Syntax:
public static boolean isLowSurrogate(char ch)
Parameters: The function accepts one mandatory parameter ch which specifies the character to be tested.
Return Value: The function returns a boolean value. The value returned is True if the char value is between MIN_LOW_SURROGATE and MAX_LOW_SURROGATE inclusive, False otherwise.
Below programs illustrate the Character.isLowSurrogate() method:
Program 1:
// Java program to illustrate the// Character.isLowSurrogate() methodimport java.lang.*;  public class gfg {      public static void main(String[] args)    {          // create 2 char primitives c1, c2        char c1 = '\udc25', c2 = 'h';          // assign isLowSurrogate results of        // c1, c2 to boolean primitives bool1, bool2        boolean bool1 = Character.isLowSurrogate(c1);        System.out.println("c1 is a Unicode low-surrogate ? " + bool1);          boolean bool2 = Character.isLowSurrogate(c2);        System.out.println(c2 + " is a Unicode low-surrogate ? " + bool2);    }} |
c1 is a Unicode low-surrogate ? true h is a Unicode low-surrogate ? false
Program 2:
// Java program to illustrate the// Character.isLowSurrogate() methodimport java.lang.*;  public class gfg {      public static void main(String[] args)    {          // create 2 char primitives c1, c2        char c1 = '\udc29', c2 = 'x';          // assign isLowSurrogate results of        // c1, c2 to boolean primitives bool1, bool2        boolean bool1 = Character.isLowSurrogate(c1);        System.out.println("c1 is a Unicode low-surrogate ? " + bool1);          boolean bool2 = Character.isLowSurrogate(c2);        System.out.println(c2 + " is a Unicode low-surrogate ? " + bool2);    }} |
c1 is a Unicode low-surrogate ? true x is a Unicode low-surrogate ? false
Reference: https://docs.oracle.com/javase/7/docs/api/java/lang/Character.html#isLowSurrogate(char)
