String:- It is predefined Java class which provide immutable object means we can not change value of String from actual address.
In Java We can write String using two different ways:-
1 String as a Object:-
String s = new String();
2 String as a Reference:-
String s = "hello";
Program Explanation of String:-
public class StringExample {
public static void main(String[] args) {
String s1 = "hello";
String s = new String("hello");
String s2=s.concat("world");
String s3= s.toUpperCase();
System.out.println(s);
System.out.println(s1);
System.out.println(s2);
System.out.println(s3);
}
}
Program Explanation of String with equals():-
equals() is used to compare two different String object ,it will return value of current address.
public class StringExample {
public static void main(String[] args) {
String s = "hello";
String s1 = new String("hello");
String s2 = new String("hello");
String s3="hello";
// System.out.println(s1.hashCode());
// System.out.println(s2.hashCode());
if(s1.equals(s3))
{
System.out.println("Equalls");
}
else
{
System.out.println("Not equalls");
}
}
}
note:- == operator never use to compare objects ,it's only for value type elements(int,char,float ,double) and String reference.
String Buffer:-
It provide mutable object because we can change value of String object from actual address.
String Buffer provide Synchronized object.
StringBuffer sb = new StringBuffer("hello");
sb.append("manish");
sout(sb);
Solution:-
public class StringExample {
public static void main(String[] args) {
StringBuffer sb = new StringBuffer("hello");
sb.append("world");
System.out.println(sb);
}
}
String Builder:-
StringBuilder is predefine class ,it also provide mutable object but it can not be synchronized ,StringBuffer is the modified format of StringBuilder class.
StringBuilder sb = new StringBuilder("manish");
sb.append("sharma");
sout(sb);
In Java We can write String using two different ways:-
1 String as a Object:-
String s = new String();
2 String as a Reference:-
String s = "hello";
Program Explanation of String:-
public class StringExample {
public static void main(String[] args) {
String s1 = "hello";
String s = new String("hello");
String s2=s.concat("world");
String s3= s.toUpperCase();
System.out.println(s);
System.out.println(s1);
System.out.println(s2);
System.out.println(s3);
}
}
Program Explanation of String with equals():-
equals() is used to compare two different String object ,it will return value of current address.
public class StringExample {
public static void main(String[] args) {
String s = "hello";
String s1 = new String("hello");
String s2 = new String("hello");
String s3="hello";
// System.out.println(s1.hashCode());
// System.out.println(s2.hashCode());
if(s1.equals(s3))
{
System.out.println("Equalls");
}
else
{
System.out.println("Not equalls");
}
}
}
note:- == operator never use to compare objects ,it's only for value type elements(int,char,float ,double) and String reference.
String Buffer:-
It provide mutable object because we can change value of String object from actual address.
String Buffer provide Synchronized object.
StringBuffer sb = new StringBuffer("hello");
sb.append("manish");
sout(sb);
Solution:-
public class StringExample {
public static void main(String[] args) {
StringBuffer sb = new StringBuffer("hello");
sb.append("world");
System.out.println(sb);
}
}
String Builder:-
StringBuilder is predefine class ,it also provide mutable object but it can not be synchronized ,StringBuffer is the modified format of StringBuilder class.
StringBuilder sb = new StringBuilder("manish");
sb.append("sharma");
sout(sb);
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