package changed;import javax.swing.UIManager;import java.awt.*;public class Changed {  int changeInt(int x){    x++;    //return x;    System.out.print("a="+x);  }  void changeDouble(double y){    y*=1.2;    System.out.print("  b="+y);  }  void changeChar(char c){    c='w';    System.out.print("  c="+c);  }  void changeBoolean(boolean b){    b=!b;    System.out.print("  d="+b);  } public static void main(String[] args) {  int a=2;  double b=5.3f;  char c='e';  boolean d=true;  System.out.println("before change:");  System.out.println("a="+a+"  b="+b+"  c="+c+"  d="+d);  Changed cha=new Changed(); // 創建一個 change 類型的對象 cha  System.out.println("after change:");  cha.changeInt(3); System.out.print("a="+a);  cha.changeDouble(b);  cha.changeChar(c);  cha.changeBoolean(d);  }}