What would be the most efficient way to construct a new String using a Character[]? It's easy enough to do with the primitive char[], but unfortunately the String constructor does not include an option for Character[]. Converting to a char[] seems cumbersome. Is there any efficient way to construct the String with just the Character[]?
Thanks.
One solution is to use a Stream with Collectors#joining:
Character[] chars = { 'H', 'e', 'l', 'l', 'o' };
String s = Arrays.stream(chars)
.map(Object::toString)
.collect(Collectors.joining());
System.out.println(s);
Output:
Hello
One way of converting Character array to String
Character[] chars = { 'H', 'e', 'l', 'l', 'o' };
String str = Stream.of(chars)
.map(String::valueOf)
.collect(Collectors.joining());
System.out.println(str);
Ouput:
Hello
/*
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* and open the template in the editor.
*/
package javaapplication2;
public class as {
public static void main(String[] args) {
Character[] chars = {'T', 'e', 'c', 'h', 'i', 'e', ' ',
'D', 'e', 'l', 'i', 'g', 'h', 't'};
StringBuilder word=new StringBuilder();
for (Character char1 : chars) {
word.append(char1);
}
System.out.println(word);
}
}
Character[], not char[].Is there any efficient way to construct the String with just the
Character[]?
No. There are no constructors which can do that.
The most efficient approach is likely to be converting it to char[] as you yourself suggested:
char[] chars = new char[characters.length];
for (int i = characters.length - 1; i >= 0; i--) {
chars[i] = characters[i];
}
String s = String.valueOf(chars);
Remember that “efficient” does not mean “stuffed into one line.” A Stream-based solution is going to be less efficient, because it will create (and eventually garbage-collect) a String for each Character.
StringBuilder s = new StringBuilder(chars.length())followed by a loop whose body callss.appendis as efficient as you’re likely to get. Any shorter solutions will be doing the equivalent at best.