Permutations in JOptionPane

Question

import javax.swing.JOptionPane;
public class Permutations {

public static void main(String[] args) throws Exception {
    String str = null;
    str = JOptionPane.showInputDialog("Enter a word");
    StringBuffer strBuf = new StringBuffer(str);
    doPerm(strBuf,str.length());

}

private static void doPerm(StringBuffer str, int index){
    String[] anArrayOfStrings;  
    if(index == 0){ 
        System.out.println(str);
        }      
    else { 
        doPerm(str, index-1);
        int currPos = str.length()-index;
        for (int i = currPos+1; i < str.length(); i++) {
            swap(str,currPos, i);
            doPerm(str, index-1);
            swap(str,i, currPos);
        } 
    }       

}


private  static void swap(StringBuffer str, int pos1, int pos2){
    char t1 = str.charAt(pos1);
    str.setCharAt(pos1, str.charAt(pos2));
    str.setCharAt(pos2, t1);
} 

}

Using the code above I permutate a word and print them in console.

Sample Input: bad

Output:

bad
bda
abd
adb
dab
dba

I want to show the output in JOptionPane. I tried to replace this line

System.out.println(str);

With this

JOptionPane.showMessageDialog(null, str);

But the all the output does not load in 1 JOptionPane. Instead it show me a JOptionPane with 'bad' and when I click OK or press Enter a JOptionPane with 'bda' will show and so on until it finish the loop. What I want is to show the 6 output in single JOptionPane.

I also try like array but almost the same output.

    private static void doPerm(StringBuffer str, int index){
    ArrayList<String> list = new ArrayList<String>();
    if(index == 0){ 
        list.add(str.toString());
        }      
    else { 
        doPerm(str, index-1);
        int currPos = str.length()-index;
        for (int i = currPos+1; i < str.length(); i++) { 
            swap(str,currPos, i);
            doPerm(str, index-1);
            swap(str,i, currPos);
        } 
    }
    JOptionPane.showMessageDialog(null, list);

}

Answer 1

I guess you are looking for something like this:

You should proceed as follows:

import javax.swing.JOptionPane;
public class Permutation {

public static void main(String[] args) throws Exception {
    String str = null;
    str = JOptionPane.showInputDialog("Enter a word");
    StringBuffer strBuf = new StringBuffer(str);
    doPerm(strBuf,str.length());
    JOptionPane.showMessageDialog(null,sbuf.toString());
}
static StringBuffer sbuf = new StringBuffer();
private static void doPerm(StringBuffer str, int index){
    String[] anArrayOfStrings;  
    if(index == 0){ 
        //System.out.println(str);
        sbuf.append(str+"\n");
        }      
    else { 
        doPerm(str, index-1);
        int currPos = str.length()-index;
        for (int i = currPos+1; i < str.length(); i++) {
            swap(str,currPos, i);

            doPerm(str, index-1);
            swap(str,i, currPos);
        } 
    }       

}


private  static void swap(StringBuffer str, int pos1, int pos2){
    char t1 = str.charAt(pos1);
    str.setCharAt(pos1, str.charAt(pos2));
    str.setCharAt(pos2, t1);
} 

}