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Take a look at String.format. Note, however, that it takes format specifiers similar to those of C's printf family of functions -- for example:

String.format("Hello %s, %d", "world", 42);

…would return "Hello world, 42". The "format string" link points to the complete official spec, but for simple cases, this much shorter documentation may be helpful for an introduction to format specifiers even though it's outdated and about Lava. The most commonly used ones are:

%s - insert a string
%d - insert a signed integer (decimal)
%f - insert a real number, standard notation

This is radically different from C#, which uses positional references with an optional format specifier. That means that you can't do things like:

String.format("The {0} is repeated again: {0}", "word");

... without actually repeating the parameter passed to printf/format. (see The Scrum Meister's comment below)

If you just want to print the result directly, you may find System.out.printf (PrintStream.printf) to your liking.

Answer from Martin Törnwall on Stack Overflow

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How to format strings in Java - Stack Overflow

Top answer

1 of 12

323

Take a look at String.format. Note, however, that it takes format specifiers similar to those of C's printf family of functions -- for example:

String.format("Hello %s, %d", "world", 42);

%s - insert a string
%d - insert a signed integer (decimal)
%f - insert a real number, standard notation

This is radically different from C#, which uses positional references with an optional format specifier. That means that you can't do things like:

String.format("The {0} is repeated again: {0}", "word");

... without actually repeating the parameter passed to printf/format. (see The Scrum Meister's comment below)

If you just want to print the result directly, you may find System.out.printf (PrintStream.printf) to your liking.

2 of 12

182

In addition to String.format, also take a look java.text.MessageFormat. The format less terse and a bit closer to the C# example you've provided and you can use it for parsing as well.

For example:

int someNumber = 42;
String someString = "foobar";
Object[] args = {new Long(someNumber), someString};
MessageFormat fmt = new MessageFormat("String is \"{1}\", number is {0}.");
System.out.println(fmt.format(args));

A nicer example takes advantage of the varargs and autoboxing improvements in Java 1.5 and turns the above into a one-liner:

MessageFormat.format("String is \"{1}\", number is {0}.", 42, "foobar");

MessageFormat is a little bit nicer for doing i18nized plurals with the choice modifier. To specify a message that correctly uses the singular form when a variable is 1 and plural otherwise, you can do something like this:

String formatString = "there were {0} {0,choice,0#objects|1#object|1<objects}";
MessageFormat fmt = new MessageFormat(formatString);
fmt.format(new Object[] { new Long(numberOfObjects) });

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Hello, so I have a question to check whether a number is a palindrome or not, (a palindrome is a number that you read the same if you read it digit by digit from left to right or vice versa). keeping in mind you must enter only 5 digits, However I don't know how to deal with it if the user enters 0 for example 02120 is palindrome, however, java omit the first zero so it's considered as a non palindrome.

Here is what I managed to so so far but it doesn't work with numbers starting with 0 .

thank you.