Data Type / Primitives
/**
* JAVA PRIMITIVES - INTEGER DATA TYPES
* ------------------------------------
*
* Java has 8 primitive data types:
* - char, boolean, byte, short, int, long, float, double
*
* We focus on the primitives used to store whole numbers (integers):
* - byte : 8-bit signed integer
* - short: 16-bit signed integer
* - int : 32-bit signed integer
* - long : 64-bit signed integer
*
* These types differ mainly in how much memory they use
* and the range of vaues they can store.
* --------------------------------------
*/
package com.minte9.basics.data_types;
public class Primitives {
public static void main(String[] args) {
/**
* ------------------------------------------------------
* byte overflow
* ------------------------------------------------------
* Range: -128 to 127
* Commonly used when memory is very limited
*/
byte maxByte = 127;
System.out.println("byte max value: " + maxByte); // 127
maxByte++; // overflow
System.out.println("after overflow: " + maxByte); // -128
/**
* ------------------------------------------------------
* short overflow
* ------------------------------------------------------
* Size: 16 bits
* Range: -32,768 to 32,767
*
* Commonly used when memory is very limited.
*/
short maxShort = 32_767;
System.out.println("short max value: " + maxShort);
maxShort++; // overflow
System.out.println("after overflow: " + maxShort); // -32768
/**
* ------------------------------------------------------
* int overflow
* ------------------------------------------------------
* Size: 32 bits
* Range: -2,147,483,648 to 2,147,483,647
*
* Default and most commonly used integer type in Java.
*/
int maxInt = Integer.MAX_VALUE;
System.out.println("int max value: " + maxInt);
maxInt++; // overflow
System.out.println("after overflow: " + maxInt); // -2147483648
/**
* ------------------------------------------------------
* long overflow
* ------------------------------------------------------
* Size: 64 bits
* Range: -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
*
* Used when int is not large enough.
* Long literals must end with L.
*/
long maxLong = 9_000_000_000L;
System.out.println("int max value: " + maxLong);
maxLong++; // overflow
System.out.println("after overflow: " + maxLong); // 9000000001
/**
* ------------------------------------------------------
* Preventing overflow
* ------------------------------------------------------
* Use Math.addExact() to throw an exception instead of
* silently overflow.
*/
try {
int safeSum = Math.addExact(Integer.MAX_VALUE, 1);
System.out.println("safe sum: " + safeSum);
} catch (ArithmeticException e) {
System.out.println("Overflow detected!");
}
// ---------------------------------------
// Overflow detected!
}
}
