how to convert char to string

Question

I have a word as string that want to take a character of it and assign it as the button name. As you know button only accepts String.

    String possibleLetters = "asdaAsadWERWasdas";
    for (int i = 0; i <= possibleLetters.length(); i++)
        {
            String bottonName = possibleLetters.charAt(i);
            JButton letterBottons = new JButton(bottonName);

        }

Answer 1

尝试：

JButton letterBottons = new JButton(Character.toString(bottonName));

Answer 2

Another way to do it is:

String possibleLetters = "asdaAsadWERWasdas";
for (int i = 0; i <= possibleLetters.length(); i++) {
    String buttonName = possibleLetters.substring(i, i + 1);
    JButton letterButtons = new JButton(buttonName);
}

Depending on the implementation ¹ of the String class, this might give you marginally better performance.

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^{1 - In older versions of Java, the substring method would create a String object that shared its backing array with the original one. By constrast the Character.toString() method creates a string with its own (newly allocated) backing array. This changes in Java 7. Now the substring creates a String that does NOT share its backing array. This neatly illustrates why this level of micro-optimization can be a waste of time in the long term.}