How to convert a char to a String?

You can use Character.toString(char). Note that this method simply returns a call to String.valueOf(char), which also works.

As others have noted, string concatenation works as a shortcut as well:

String s = "" + 's'; 

But this compiles down to:

String s = new StringBuilder().append("").append('s').toString(); 

which is less efficient because the StringBuilder is backed by a char[] (over-allocated by StringBuilder() to 16), only for that array to be defensively copied by the resulting String.

String.valueOf(char) "gets in the back door" by wrapping the char in a single-element array and passing it to the package private constructor String(char[], boolean), which avoids the array copy.

I've got of the following five six methods to do it.

// Method #1 String stringValueOf = String.valueOf('c'); // most efficient // Method #2 String stringValueOfCharArray = String.valueOf(new char[]{x}); // Method #3 String characterToString = Character.toString('c'); // Method #4 String characterObjectToString = new Character('c').toString(); // Method #5 // Although this approach seems very simple, // this is less efficient because the concatenation // expands to a StringBuilder. String concatBlankString = 'c' + ""; // Method #6 String fromCharArray = new String(new char[]{x}); 

Note: Character.toString(char) returns String.valueOf(char). So effectively both are same.

String.valueOf(char[] value) invokes new String(char[] value), which in turn sets the value char array.

public String(char value[]) { this.value = Arrays.copyOf(value, value.length); } 

On the other hand String.valueOf(char value) invokes the following package private constructor.

String(char[] value, boolean share) { // assert share : "unshared not supported"; this.value = value; } 

Source code from String.java in Java 8 source code

Hence String.valueOf(char) seems to be most efficient method, in terms of both memory and speed, for converting char to String.

Sources:

1. How to convert primitive char to String in Java
2. How to convert Char to String in Java with Example

Below are various ways to convert to char c to String s (in decreasing order of speed and efficiency)

char c = 'a'; String s = String.valueOf(c); // fastest + memory efficient String s = Character.toString(c); String s = new String(new char[]{c}); String s = String.valueOf(new char[]{c}); String s = new Character(c).toString(); String s = "" + c; // slowest + memory inefficient 

Use any of the following:

String str = String.valueOf('c'); String str = Character.toString('c'); String str = 'c' + ""; 

Use the Character.toString() method like so:

char mChar = 'l'; String s = Character.toString(mChar); 

As @WarFox stated - there are 6 methods to convert char to string. However, the fastest one would be via concatenation, despite answers above stating that it is String.valueOf. Here is benchmark that proves that:

@BenchmarkMode(Mode.Throughput) @Fork(1) @State(Scope.Thread) @Warmup(iterations = 10, time = 1, batchSize = 1000, timeUnit = TimeUnit.SECONDS) @Measurement(iterations = 10, time = 1, batchSize = 1000, timeUnit = TimeUnit.SECONDS) public class CharToStringConversion { private char c = 'c'; @Benchmark public String stringValueOf() { return String.valueOf(c); } @Benchmark public String stringValueOfCharArray() { return String.valueOf(new char[]{c}); } @Benchmark public String characterToString() { return Character.toString(c); } @Benchmark public String characterObjectToString() { return new Character(c).toString(); } @Benchmark public String concatBlankStringPre() { return c + ""; } @Benchmark public String concatBlankStringPost() { return "" + c; } @Benchmark public String fromCharArray() { return new String(new char[]{c}); } } 

And result:

Benchmark Mode Cnt Score Error Units CharToStringConversion.characterObjectToString thrpt 10 82132.021 ± 6841.497 ops/s CharToStringConversion.characterToString thrpt 10 118232.069 ± 8242.847 ops/s CharToStringConversion.concatBlankStringPost thrpt 10 136960.733 ± 9779.938 ops/s CharToStringConversion.concatBlankStringPre thrpt 10 137244.446 ± 9113.373 ops/s CharToStringConversion.fromCharArray thrpt 10 85464.842 ± 3127.211 ops/s CharToStringConversion.stringValueOf thrpt 10 119281.976 ± 7053.832 ops/s CharToStringConversion.stringValueOfCharArray thrpt 10 86563.837 ± 6436.527 ops/s 

As you can see, the fastest one would be c + "" or "" + c;

VM version: JDK 1.8.0_131, VM 25.131-b11 

This performance difference is due to -XX:+OptimizeStringConcat optimization. You can read about it here.

Try this: Character.toString(aChar) or just this: aChar + ""

We have various ways to convert a char to String. One way is to make use of static method toString() in Character class:

char ch = 'I'; String str1 = Character.toString(ch); 

Actually this toString method internally makes use of valueOf method from String class which makes use of char array:

public static String toString(char c) { return String.valueOf(c); } 

So second way is to use this directly:

String str2 = String.valueOf(ch); 

This valueOf method in String class makes use of char array:

public static String valueOf(char c) { char data[] = {c}; return new String(data, true); } 

So the third way is to make use of an anonymous array to wrap a single character and then passing it to String constructor:

String str4 = new String(new char[]{ch}); 

The fourth way is to make use of concatenation:

String str3 = "" + ch; 

This will actually make use of append method from StringBuilder class which is actually preferred when we are doing concatenation in a loop.

Here are a few methods, in no particular order:

char c = 'c'; String s = Character.toString(c); // Most efficient way s = new Character(c).toString(); // Same as above except new Character objects needs to be garbage-collected s = c + ""; // Least efficient and most memory-inefficient, but common amongst beginners because of its simplicity s = String.valueOf(c); // Also quite common s = String.format("%c", c); // Not common Formatter formatter = new Formatter(); s = formatter.format("%c", c).toString(); // Same as above formatter.close(); 

I am converting Char Array to String

Char[] CharArray={ 'A', 'B', 'C'}; String text = String.copyValueOf(CharArray); 

 char vIn = 'A'; String vOut = Character.toString(vIn); 

For these types of conversion, I have site bookmarked called https://www.converttypes.com/ It helps me quickly get the conversion code for most of the languages I use.

I've tried the suggestions but ended up implementing it as follows

editView.setFilters(new InputFilter[]{new InputFilter() { @Override public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) { String prefix = "http://"; //make sure our prefix is visible String destination = dest.toString(); //Check If we already have our prefix - make sure it doesn't //get deleted if (destination.startsWith(prefix) && (dstart <= prefix.length() - 1)) { //Yep - our prefix gets modified - try preventing it. int newEnd = (dend >= prefix.length()) ? dend : prefix.length(); SpannableStringBuilder builder = new SpannableStringBuilder( destination.substring(dstart, newEnd)); builder.append(source); if (source instanceof Spanned) { TextUtils.copySpansFrom( (Spanned) source, 0, source.length(), null, builder, newEnd); } return builder; } else { //Accept original replacement (by returning null) return null; } } }}); 

To convert a char to a String, you can use the String.valueOf method.

To convert a String to a char, you can use the String.charAt method.

char character = 'a'; String string = String.valueOf(character); 

String string = "a"; char character = string.charAt(0); 

Just chipping in to add that with rust 1.46.0 you can convert a char into a string like so:

let string = String::from('a');