How to convert String into primitive data types and primitive data types into String

#Topic-7

Previous topic (6) we have discussed about Wrapper class, auto-boxing, UN-boxing and other related topics. If you have not gone through that topic, click this link Wrapper class, auto-boxing, UN-boxing in Java?

In this section we will discuss about How to convert String into primitive data types and primitive data types into String.

How to convert String into primitive data type:
Note: value should be compatible to destination type (we can’t convert “java” into int) 
//1st way

Example of convert String to Integer: 

String str1 = "5";
int result = Integer.parseInt(str1); // Using Integer.parsrInt()
System.out.println(result);

Example of convert String to Double:

String str=”125”;
double a1=Double.parseDouble(str);

System.out.println(a1); 

Example of convert String to Boolean:

String a=”true”;
boolean a=Boolean.parseBoolean(a); 

System.out.println(a);  

Example of convert String to Char array:

String a=”java”;
char[] ch=a.toCharArray(); 

//2nd way
Example of convert String to Integer: 
String str2 = "5";
Integer result2 = Integer.valueOf(str2); // Using Integer.valueOf()
System.out.println(result2);

Example of convert String to Double:

String str=”125”;
double a1=Double.valueOf(a1);

System.out.println(a1); 

Example of convert  String to Boolean:

String a=”true”;
boolean a=Boolean.valueOf(a); 

System.out.println(a); 

How to convert primitive data type into String:
//1st way

Example of convert Integer to String:
int x = 5;

String str = Integer.toString(x);  // using Integer.toString()
System.out.println(str); 

Example of convert Double to String:
double d=150.25;
String s1=Double.toString(d);

System.out.println(s1);

//2nd way

Example of convert Integer to String:
int x = 5;

String str2 = String.valueOf(x);    // using String.valueOf()
System.out.println(str2); 

Example of convert Double to String:
double d=150.25;
String s1=String.valueOf(d);

System.out.println(s1); 

What is Next?
In the next section, we will be going through Class , constructor ans this keyword in Java

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