String[] s={"aa","ss","zz"}; ArrayList[] attr_name = null;
try {
attr_name[0].add(s[0]);
attr_name[0].add(s[1]);
attr_name[0].add(s[2]);
System.out.print(attr_name[0].get(0));
} catch (Exception e) {
// TODO: handle exception
}
为什么打印不出数据?请大家指点谜精!
try {
attr_name[0].add(s[0]);
attr_name[0].add(s[1]);
attr_name[0].add(s[2]);
System.out.print(attr_name[0].get(0));
} catch (Exception e) {
// TODO: handle exception
}
为什么打印不出数据?请大家指点谜精!
String[] s={"aa","ss","zz"};ArrayList[] attr_name = null;
try {
attr_name[0].add(s[0]);//这里出异常,跳到TODO处
attr_name[0].add(s[1]);
attr_name[0].add(s[2]);System.out.print(attr_name[0].get(0));} catch (Exception e) {
// TODO: handle exception
}
为什么打印不出数据?请大家指点谜精!
attr_name[0].add(s[0]);//这应该会有空指针异常 ArrayList[] attr_name=new ArrayList();
attr_name[0].add(s[0]);前先new个对象
ArrayList[] attr_name = null;
try
{
attr_name[0] = new ArrayList(); attr_name[0].add(s[0]);
attr_name[0].add(s[1]);
attr_name[0].add(s[2]); System.out.println(attr_name[0].get(0));
}
catch(Exception e)
{
System.out.println(e);
}