public class Retger
{
public static void change(StringBuffer a,StringBuffer b)
{
a = new StringBuffer("333");
a.append(b);
//a=a+b;
b=a;
}
public static void main(String args[])
{
StringBuffer a= new StringBuffer("A");
StringBuffer b= new StringBuffer("B");
change(a,b);
System.out.println(a+","+b);
}
}
问 为什么a.append(b);后a会改变,而a=a+b;后a没变化!(望详细)
{
public static void change(StringBuffer a,StringBuffer b)
{
a = new StringBuffer("333");
a.append(b);
//a=a+b;
b=a;
}
public static void main(String args[])
{
StringBuffer a= new StringBuffer("A");
StringBuffer b= new StringBuffer("B");
change(a,b);
System.out.println(a+","+b);
}
}
问 为什么a.append(b);后a会改变,而a=a+b;后a没变化!(望详细)
{
public static StringBuffer change(StringBuffer a,StringBuffer b)
{
a = new StringBuffer("333");
a.append(b);
//a=a+b;
b=a;
return a;
}
public static void main(String args[])
{
StringBuffer a= new StringBuffer("A");
StringBuffer b= new StringBuffer("B");
a = change(a,b);
System.out.println(a);
}
}
public static void change(StringBuffer a,StringBuffer b)
{
a = new StringBuffer("333");
System.out.println(a+" , "+b);
a.append(b);
//a=a+b;
b=a;
System.out.println(a+" , "+b);
}
public static void main(String args[])
{
StringBuffer a= new StringBuffer("A");
StringBuffer b= new StringBuffer("B");
change(a,b);
System.out.println(a+" , "+b);
}
}
结果:
333 , B
333B , 333B
A , B
StringBuffer a = "",b = "";
a = a + b;
我记得好像StringBuffer是不能相加的吧。
a.append(b),a对象还是a对象,只是将b的数据追加到a的数据的后面.