老生常谈反射之Class类的使用(必看篇)

Class c1 = Foo.class; 

Foo foo1 = new Foo(); 2 Class c2 = foo1.getClass(); 

Class c3 = null;
try {
  c3 = Class.forName("com.format.test.Foo");
} catch (ClassNotFoundException e) {
  e.printStackTrace();
}

try {
  Foo foo2 = (Foo) c1.newInstance(); //需要有无参构造
} catch (InstantiationException e) {
  e.printStackTrace();
} catch (IllegalAccessException e) {
  e.printStackTrace();
}