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Get next lexicographic character

Is there a method of java characters that will return the next character in lexicographical order?
char x = 'a'.next();
'a'.next() would return b. 'b'.next() would return c. etc.

char x = 'a';
System.out.println(++x);
Output: b
I hope this is enough as a hint.
Basically, just increase the ASCII code of char variable to get the next char.
And yes, ASCII code is basically just an integer. (Try doing System.out.println((int) 'a'); and you will get output as 97, which is the ASCII value for char a). Similarly, every char has some ASCII value.

In Java, how do I set each character as an integer?

I would like to put the entire alphabet from A-Z into an array of 0 to 25. From then I would like to manipulate it. So, for example if the user input a character and a number, I would be able to move that character by a certain amount on the alphabet.
For example the letter "A" and the number "3" will give me the letter "D" in the end.
How should I implement this? Thank you!

There is no need for an array. In Java, a char is an integral type. So you could use something like
int count = 3;
char out = (char) ('A' + (count % ('Z' - 'A')));
System.out.println(out);
Output is (as requested)
D

You can write directly 'A' + n:
char getChar(int n) {
return 'A' + n;
}
If the input is not necessarily correct you can add your conditions.

You could use the ASCII value of the letters.
A=65
B=66....
Take the char you need to know the value and do ('A' - 'A' + 1) +3
Replace the first A by any letter you need the value of

How to get a character from a number in Java

Hi I want the opposite function of getNumericValue
int i = Character.getNumericValue('A');
if('A' == Character.someFunction(i)){
System.out.println("hooray");
}
I have tried "Character.forDigit" but this seems to be completely wrong.
Am new to java so please help.

The opposite is Character.forDigit
if(Character.forDigit(Character.getNumericValue('b'), Character.MAX_RADIX) == 'b') {
// true!
}
if(Character.forDigit(Character.getNumericValue('B'), Character.MAX_RADIX) == 'b') {
// true!
}
if(Character.getNumericValue('B') == Character.getNumericValue('b')) {
// true!
}
if((int)('B') == (int)'b') {
// false
}
Although given your question I think your looking for the actual ASCII char code for the letter.
Read this Java Character literals value with getNumericValue() post to see more information about Character.getNumericValue

To convert between char and int you can use typecasting. For example:
char myChar = (char) 65;
System.out.println(myChar);
will result in A. Hope that helps!

Character.getNumericValue('A') convert 'A' into unicode representation of the char. Probably you don't want to use that.
The letters A-Z in their uppercase ('\u0041' through '\u005A'),
lowercase ('\u0061' through '\u007A'), and full width variant
('\uFF21' through '\uFF3A' and '\uFF41' through '\uFF5A') forms have
numeric values from 10 through 35. This is independent of the Unicode
specification, which does not assign numeric values to these char
values.

Java-Function to print the variable with a particular ASCII code

I have to write a Java program for cryptography which takes a number from the user and adds( or subtracts the number if it is negative) from the ASCII code of the character. For example if the number taken is 2, and the given string is "ABCZ" it should return "CDEB".
I've figured out most of it, but I'm not sure how to return the character which has a given ASCII code. So if the ASCII is 65,how do I return "A"?
I'm only in class 10,so please keep it as simple as possible. Thanks in advance.

All you need is to cast the number to a character.
int yourInt = 65;
char ch = (char) yourInt;
System.out.println(yourInt);
System.out.println(ch);
// Output:
// 65
// A

Character literal in Java?

So I just started reading "Java In A Nutshell", and on Chapter One it states that:
"To include a character literal in a Java program, simply place it between single quotes"
i.e.
char c = 'A';
What exactly does this do^? I thought char only took in values 0 - 65,535. I don't understand how you can assign 'A' to it?
You can also assign 'B' to an int?
int a = 'B'
The output for 'a' is 66. Where/why would you use the above^ operation?
I apologise if this is a stupid question.
My whole life has been a lie.

char is actually an integer type. It stores the 16-bit Unicode integer value of the character in question.
You can look at something like http://asciitable.com to see the different values for different characters.

In Java char literals represent UTF-16 (character encoding schema) code units. What you got from UTF-16 is mapping between integer values (and the way they are saved in memory) with corresponding character (graphical representation of unit code).
You can enclose characters in single quotes - this way you don't need to remember UTF-16 values for characters you use. You can still get the integer value from character type and put if for example in int type (but generally not in short, they both use 16 bits but short values are from -32768 to 32767 and char values are from 0 to 65535 or so).

If you look at an ASCII chart, the character "A" has a value of 41 hex or 65 decimal. Using the ' character to bracket a single character makes it a character literal. Using the double-quote (") would make it a String literal.
Assigning char someChar = 'A'; is exactly the same as saying char someChar = 65;.
As to why, consider if you simply want to see if a String contains a decimal number (and you don't have a convenient function to do this). You could use something like:
bool isDecimal = true;
for (int i = 0; i < decString.length(); i++) {
char theChar = decString.charAt(i);
if (theChar < '0' || theChar > '9') {
isDecimal = false;
break;
}
}