Question

我读了这个教程： http://jroller.com/eyallupu/entry/two_side_notes_about_arrays

但仍然无法弄清楚如何区分基元，数组和类（反射）

例如：我有以下课程：

class MainClass {

    public MainClass() {
        memberSubClass = new SubClass();
        arrayMemberSubClass = new SubClass[3];
        for (int i = 0; i < 3; i++) {
            arrayMemberSubClass[i] = new SubClass();
        }
        array_int_member = new int[5];
    }

    class SubClass {
        public int x;
        public short y;
    }

    public SubClass memberSubClass;
    public SubClass[] arrayMemberSubClass;
    public int int_member;
    public int[] array_int_member;
}

我有以下方法（在其他课程中）：

public void doSometing(Object obj) {

    Field[] fields = obj.getClass().getFields();
    for (Field field : fields) {    
        if (field.getType().isArray()) {
                if (field.getType().isPrimitive()) {
                    logger.debug(field.getName() + " is array of primitives");
                } else {
                    logger.debug(field.getName() + " is array of classes");
                }       
            }   
            else {
                if (field.getType().isPrimitive()) {
                    logger.debug(field.getName() + " is primitives");
                } else {
                    logger.debug(field.getName() + " is class");
                }       
            }
    }
}

输出结果为：

0 [main] DEBUG Logic  - memberSubClass is class
1 [main] DEBUG Logic  - arrayMemberSubClass is array of classes
1 [main] DEBUG Logic  - int_member is primitives
1 [main] DEBUG Logic  - array_int_member is array of classes

我希望得到以下结果：

0 [main] DEBUG Logic  - memberSubClass is class
1 [main] DEBUG Logic  - arrayMemberSubClass is array of classes
1 [main] DEBUG Logic  - int_member is primitives
1 [main] DEBUG Logic  - array_int_member is array of primitives

我做错了什么？

Answer 1

从您引用的页面：

One thing I think was missing in the post is how to get the type of the array elements using reflection. This can be done using the getComponentType() method:

Boolean[] b = new Boolean[5];
Class<?> theTypeOfTheElements = b.getClass().getComponentType();
System.out.println(theTypeOfTheElements.getName());

java我们怎么知道field是否是内部类的数组？

1 个答案: