StringBuilder Practice
//Java.lang.StringBuilder.substring() Method
//Description:
// The java.lang.StringBuilder.substring(int start, int end) method returns a new
// String that contains a subsequence of characters currently contained in this sequence.
// The substring begins at the specified start and extends to the character at index end - 1.
//Declaration
public String substring(int start, int end)
//Parameters
//start -- This is the beginning index, inclusive.
//end -- This is the ending index, exclusive.
//Return Value
//This method returns the new string.
//Exception
StringIndexOutOfBoundsException
//-- if start or end are negative or greater than length(), or start is greater than end.
//Example
package com.tutorialspoint;
import java.lang.*;
public class StringBuilderDemo {
public static void main(String[] args) {
StringBuilder str = new StringBuilder("admin");
System.out.println("string = " + str);
// prints substring from index 3
System.out.println("substring is = " + str.substring(3));
/* prints substring from index 1 to 4 excluding character
at 4th index */
System.out.println("substring is = " + str.substring(1, 4));
}
}
Let us compile and run the above program, this will produce the following result:
string = admin
substring is = in
substring is = dmi
Java.lang.StringBuilder.insert() Method
// Description
// The java.lang.StringBuilder.insert(int offset, String str) method inserts the
// string into this character sequence.
// The characters of the String argument are inserted, in order, into this sequence
// at the indicated offset, moving up any characters originally above that position
// and increasing the length of this sequence by the length of the argument.
//Declaration
public StringBuilder insert(int offset, String str)
//Parameters
// offset -- This is the offset.
// str -- This is the value of string.
//Return Value
//Exception
StringIndexOutOfBoundsException -- if the offset is invalid.
//Example
package com.tutorialspoint;
import java.lang.*;
public class StringBuilderDemo {
public static void main(String[] args) {
StringBuilder str = new StringBuilder("tutorials website");
System.out.println("string = " + str);
// insert string value at offset 9
str.insert(9, "point");
// prints StringBuilder after insertion
System.out.print("After insertion = ");
System.out.println(str.toString());
}
}
//Let us compile and run the above program, this will produce the following result:
string = tutorials website
After insertion = tutorialspoint website
Given:
StringBuilder b1 = new StringBuilder("snorkler");
StringBuilder b2 = new StringBuilder("yoodler");
b1.replace(3, 4, b2.substring(4).append(b2.append(false)));
//b1 = "snorkler" b2 = "yoodlerfalse"
b1.replace(3, 4, b2.substring(4).append("yoodlerfalse"));
//b1 = "snorkler" b2 = "lerfalseyoodlerfalse"
b1.replace(3, 4, "lerfalseyoodlerfalse");
//b1 = "snolerfalseyoodlerfalsekler" b2 = "lerfalseyoodlerfalse"
Given:
StringBuilder b1 = new StringBuilder("snorkler");
StringBuilder b2 = new StringBuilder("yoodler");
b2.insert(3, b1.append("a"));
//b1 = snorklera //b2 = yoodler
b2, insert(3, "snorklera");
//b1 = snorklera //b2 = yoosnorkleradler
Given:
StringBuilder b1 = new StringBuilder("snorkler");
StringBuilder b2 = new StringBuilder("yoodler");
b1.append(b2.substring(2,5).toUpperCase());
//b1 = snorkler b2 = yoodler
b1.append("odl".toUpperCase());
//b1 = snorkler b2 = yoodler
b1.append("ODL");
//b1 = snorklerODL b2 = yoodler