为什么输出a是AB,而b是B
public class test {
public static void operate(StringBuffer x,StringBuffer y){
x.append(y);
y=x;
}
public static void main(String[] args) {
StringBuffer a= new StringBuffer("A");
StringBuffer b= new StringBuffer("B");
operate(a,b);
System.out.println("a="+a);
System.out.println("b="+b);
}
}
为什么输出a是AB,而b是B