Java Programming Examples - Data Types

Exercise 1: Declare and initialize both Primitive and Non-primitive data types.

package datatypes;

public class DataTypes_E1 {
public static void main(String[] args) {
dataTypes();
}

public static void dataTypes() {
int x=10;
char ch='x';
String s="AutoTechX";
boolean b=true;
float f = 5.5f;
double d = 10.15d;
byte by=20;
short sh=30;
int[] Array1_int={1,2,3};
char[] Array2_char={'a','b','c'};
String[] Array3_String={"Navdeep","Singh","Rathore"};
boolean[] Array4_boolean={true,false};

System.out.println("int: "+x);
System.out.println("char: "+ch);
System.out.println("String: "+s);
System.out.println("boolean: "+b);
System.out.println("float: "+f);
System.out.println("double: "+d);
System.out.println("byte: "+by);
System.out.println("short: "+sh);
System.out.println("Array_int: "+Array1_int[0]);
System.out.println("Array_char: "+Array2_char[2]);
System.out.println("Array_String: "+Array3_String[1]);
System.out.println("Array_boolean: "+Array4_boolean[1]);
}
}

Output:

int: 10
char: x
String: AutoTechX
boolean: true
float: 5.5
double: 10.15
byte: 20
short: 30
Array_int: 1
Array_char: c
Array_String: Singh
Array_boolean: false

Exercise 2: Print Default values of both Primitive and Non-primitive data types.

package datatypes;

public class DataTypes_E2 {
int x;
char ch;
byte by;
short sh;
long l;
float f;
double d;
boolean b;
String s;

public static void main(String[] args) {

DataTypes_E2 T=new DataTypes_E2();

System.out.println("int: "+T.x);
System.out.println("char: "+T.ch);
System.out.println("byte: "+T.by);
System.out.println("short: "+T.sh);
System.out.println("long: "+T.l);
System.out.println("float: "+T.f);
System.out.println("double: "+T.d);
System.out.println("boolean: "+T.b);
System.out.println("String: "+T.s);
}
}

Output:

int: 0

char: 

byte: 0

short: 0

long: 0

float: 0.0

double: 0.0

boolean: false

String: null