String Concatenation in Java
In java, string concatenation forms a new string that is the combination of multiple strings. There are two ways to concat string in java:
By + (string concatenation) operator
By concat() method
1) String Concatenation by + (string concatenation) operator
Java string concatenation operator (+) is used to add strings. For Example:
class TestStringConcatenation1{
public static void main(String args[]){
String s="Sachin"+" Tendulkar";
System.out.println(s);//Sachin Tendulkar
}
}
Test it Now
Output:Sachin Tendulkar
The Java compiler transforms above code to this:
String s=(new StringBuilder()).append("Sachin").append(" Tendulkar).toString();
In java, String concatenation is implemented through the StringBuilder (or StringBuffer) class and its append method. String concatenation operator produces a new string by appending the second operand onto the end of the first operand. The string concatenation operator can concat not only string but primitive values also. For Example:
class TestStringConcatenation2{
public static void main(String args[]){
String s=50+30+"Sachin"+40+40;
System.out.println(s);//80Sachin4040
}
}
Test it Now
80Sachin4040
Note: After a string literal, all the + will be treated as string concatenation operator.
2) String Concatenation by concat() method
The String concat() method concatenates the specified string to the end of current string. Syntax:
public String concat(String another)
Let's see the example of String concat() method.
class TestStringConcatenation3{
public static void main(String args[]){
String s1="Sachin ";
String s2="Tendulkar";
String s3=s1.concat(s2);
System.out.println(s3);//Sachin Tendulkar
}
}