Java Reflection 常用方法

Get Class by name

```java= Class c = Class.forName("com.package.MyClass");

## 抓取泛型的 class
```java=
(Class<T>) ((ParameterizedType) getClass()
                            .getGenericSuperclass()).getActualTypeArguments()[0];

取得extends後的 class list

```java=

// gradle implementation 'org.reflections:reflections:0.10.2'

    Reflections reflections = new Reflections(CommConstant.PACKAGE_PREFIX);
    Set<Class<? extends TaskAbs>> classes = reflections.getSubTypesOf(TaskAbs.class);
    List<Class<? extends TaskAbs>> runClazzs = classes.stream()
            .filter(c -> {
                return c.getAnnotation(Component.class) != null;
            })
            .collect(Collectors.toList());
    return runClazzs;

## newInstance by Class
```java=
Class c = ...
var constructor = c.getConstructor();
            constructor.setAccessible(true);
            TaskAbs ta = constructor.newInstance(...);

Get Class Name

```java= // 一般 getName(); // my.MyObj getgetCanonicalName(); // my.MyObj getSimpleName(); // MyObj

// innerClass getName(); // my.MyObj$InnerObj getgetCanonicalName(); // my.MyObj getSimpleName(); // InnerObj

```

tags: java