To convert decimal integer to hexadecimal, use the Integer.toHexString() method. Let’s say the following is our decimal integer.int decInt = 25;The following is the usage of the Integer.toHexString() method to convert decimal integer to hexadecimal number.String myHex = Integer.toHexString(decInt);The following the complete example.Example Live Demopublic class Demo {    public static void main(String []args) {       int decInt = 25;       System.out.println("Decimal Integer = "+decInt);       String myHex = Integer.toHexString(decInt);       System.out.println("Hexadecimal = "+myHex);    } }OutputDecimal Integer = 25 Hexadecimal = 19

To convert octal to decimal number, use the Integer.parseInt() method with radix 8. Here, the radix is for Octal i.e. 8.Let’s say we have the following octal string.String myOctal = "25";To convert it to decimal, use the Integer.parseInt() method.int val = Integer.parseInt(myOctal, 8);The following is the complete example.Example Live Demopublic class Demo {    public static void main(String []args) {       String myOctal = "25";       System.out.println("Octal = "+myOctal);       int val = Integer.parseInt(myOctal, 8);       System.out.println("Decimal = "+val);    } }OutputOctal = 25 Decimal = 21

The method Integer.decode() decodes a string to an integer. It returns an Integer object holding the int value represented by the passed string value.Note − It accepts decimal, hexadecimal, and octal number.Let’s say the following is our string.String val = "2";The following is how you can decode the string to integer.Integer myInt = Integer.decode(val);Example Live Demopublic class Demo {    public static void main(String []args) {       String val = "2";       Integer myInt = Integer.decode(val);       System.out.println("Integer = " + myInt);    } }OutputInteger = 2

To convert String to long, the following are the two methods.Method 1The following is an example wherein we use parseLong() method.Example Live Demopublic class Demo {    public static void main(String[] args) {       String myStr = "5";       Long myLong = Long.parseLong(myStr);       System.out.println("Long: "+myLong);    } }OutputLong: 5Method 2The following is an example wherein we have used valueOf() and longValue() method to convert String to long.Example Live Demopublic class Demo {    public static void main(String[] args) {       String myStr = "20";       long res = Long.valueOf(myStr).longValue();       System.out.println("Long: "+res);    } }OutputLong: 20

To check for Long overflow, we need to check the Long.MAX_VALUE with the multiplied long result, Here, Long.MAX_VALUE is the maximum value of Long type in Java.Let us see an example wherein long values are multiplied and if the result is more than the Long.MAX_VALUE, then an exception is thrown.The following is an example showing how to check for Long overflow.Example Live Demopublic class Demo {    public static void main(String[] args) {       long val1 = 6999;       long val2 = 67849;       System.out.println("Value1: "+val1);       System.out.println("Value2: "+val2);       long ... Read More

To check for Long overflow, we need to check the Long.MAX_VALUE with the added long result. Here, Long.MAX_VALUE is the maximum value of Long type in Java.Let us see an example wherein long integers are added and if the result is more than the Long.MAX_VALUE, then an exception is thrown.The following is an example showing how to check for Long overflow.Example Live Demopublic class Demo {    public static void main(String[] args) {       long val1 = 80989;       long val2 = 87567;       System.out.println("Value1: "+val1);       System.out.println("Value2: "+val2);       long ... Read More

To check whether the character is ASCII 7 bit or not, check whether given value’s ASCII value is less than 128 or not.Here, we have a character.char one = '-';Now, we have checked a condition with if-else for ASCII 7-bit character.if (c < 128) { System.out.println("Given value is ASCII 7 bit!"); } else {    System.out.println("Given value is not an ASCII 7 bit!"); }The following is an example wherein we check a character for ASCII 7-bit.Example Live Demopublic class Demo {    public static void main(String []args) {       char c = '-';       System.out.println("Given value = ... Read More

To check whether the entered value is ASCII 7-bit control character, check the characters ASCII value before 32 and 127. These are the control characters.Here, we have a character.char one = ' n ';Now, we have checked a condition with if-else to check for character less than 32 (ASCII) and equal to 127.if (one < 32 || one == 127) { System.out.println("Given value is a control character!"); } else {    System.out.println("Given value is not a control character!"); }Example Live Demopublic class Demo {    public static void main(String []args) {       char one = '';       ... Read More

To check whether the entered value is ASCII 7-bit alphabetic, check the character from ‘a’ to ‘z’ or ‘A’ to ‘Z’.Here, we have a character.char one = 'r';Now, we have checked a condition with if-else to check for character from ‘a’ to ‘z’ or ‘A’ to ‘Z’.if ((one >= 'A' && one = 'a' && one = 'A' && one = 'a' && one = 'A' && one = 'a' && one

To check whether the entered value is ASCII 7-bit alphabetic uppercase, check the character from ‘A’ to ‘Z’.Here, we have a character.char one = 'T';Now, we have checked a condition with if-else to check for uppercase character from ‘A’ to ‘Z’if (one >= 'A' && one = 'A' && one = 'A' && one