List of frequently used Java instructions (for beginners and beginners)

List of frequently used instructions

Comment out

//Two slashes on one line

/*If there are multiple lines
With slash
Surround with an asterisk

Receive a single line of string from the keyboard

//Assign the entered string to the variable words
String words = new java.util.Scanner(;

Receive one integer from the keyboard

//Assign the entered integer to the variable value
int value = new java.util.Scanner(;

Display character string (with line break)

System.out.println("Character string to display");

Display character string (no line break)

System.out.print("Character string to display");

Convert string to integer

int n = Integer.parseInt(stringNumber);

Example: Convert 1 and 2 of character string to integer and add

String s_1 = "1";
String s_2 = "2";

//Add as a string->12 is output
System.out.println(s_1 + s_2);

//Convert to integer
int i_1 = Integer.parseInt(s_1);
int i_2 = Integer.parseInt(s_2);

//Convert to an integer and then add->3 is output
System.out.println(i_1 + i_2);
<Execution result>

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