Variable Escape sequences in java

Question

Take the example:

System.out.println("Hello  Uni\u03C0");
System.out.println("Hello Esc \\");

this gives something like

Hello Uniπ

Hello Esc \

Is there a way where I can give different values to 03C0 and \ during different iterations in a loop?

for example something like

System.out.format("Hello Esc \%c",'\\');
System.out.format("Hello Esc \%c",'\"');

I know this will give compiler error. I want to know how this can be done.

For example, I would like to print a different unicode character (say from \u0000 to \u00C3) in each iteration of a loop.

For example, I have this function that returns the 4 digit hexadecimal value of an integer:

public static String hexa(int a)
    {
    int x=a;
    String b= String.format("%x",x);
    if(b.length() == 1)
    {
    b="000"+b;
    }
    if(b.length() == 2)
    {
    b="00"+b;
    }
     if(b.length() == 3)
    {
    b="0"+b;
    }
    return b;
    }

Now I would like to join \u with hexa(i) to get different unicode character for different i

Answer 1

You don't even have to convert the integer to hex string. Leave it as an integer and use Character.toChars()

    StringBuilder sb = new StringBuilder();
    sb.append(Character.toChars(0x03C0));
    System.out.println(sb.toString());

Further example showing a for loop:

public static void main(String [] args) {
    String lineSeparator = System.lineSeparator();
    StringBuilder sb = new StringBuilder();

    for(int i = 0x03C0; i < 0x03D0; i++) {
        sb.append(Character.toChars(i)).append(lineSeparator);
    }

    System.out.println(sb.toString());
}

Output:

π
ρ
ς
σ
τ
υ
φ
χ
ψ
ω
ϊ
ϋ
ό
ύ
ώ
Ϗ

One last clarification:

System.out.println(Character.toChars(0x03C0)[0] == '\u03C0');

Output:

true

Example without StringBuilder:

String foo = "";
for(char c : Character.toChars(0x03C0)) {
    foo += c;
}
System.out.println(foo);