将字符数组转换为没有空格的字符串

Question

I'm having an issue with converting an array of characters to a string in Java. I only want to copy characters that are not empty. Take this code for example:

import java.util.*;
import java.lang.*;
import java.io.*;

class CharArrayToStringTest
{
    public static void main (String[] args) throws java.lang.Exception
    {
        // works just fine - string has 5 characters and its length is 5
        char[] word = {'h', 'e', 'l', 'l', 'o'};
        String sWord = new String(word);
        System.out.println("Length of '" + sWord + "' is " + sWord.length());

        // string appears empty in console, yet its length is 5?
        char[] anotherWord = new char[5];
        String sAnotherWord = new String(anotherWord);
        System.out.println("Length of '" + sAnotherWord + "' is " + sAnotherWord.length());
        // isEmpty() even says the blank string is not empty
        System.out.println("'" + sAnotherWord + "'" + " is empty: " + sAnotherWord.isEmpty());
    }
}

Console output:

Length of 'hello' is 5
Length of '' is 5
'' is empty: false

How do I create a string from an array of characters where any blank characters at the end of the string are left out?

Answer 1

Try trimming the trailing spaces in the String using String.trim() . Just do : -

char[] anotherWord = new char[5];
String sAnotherWord = new String(anotherWord);
sAnotherWord = sAnotherWord.trim();

Now, the spaces would be removed.

Edit 1 : As mention by spencer.sm in his answer, your second print statement is faulty, as it prints sWord.length() instead of sAnotherWord.length() .

Answer 2

You cannot have an empty char in Java. All chars must be exactly one character. If you want to remove whitespace at the end of a string, use the String trim() method.

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Also, your second print statement should end with sAnotherWord.length() instead of sWord.length() . See below:

System.out.println("Length of '" + sAnotherWord + "' is " + sAnotherWord.length());