How do I get the reference type corresponding to a primitive type?

Question

我想要一个将类映射到类的函数，例如int.class-> Integer。

Answer 1

Primitives.wrap(Class) JDK中没有专门提供此功能，但是如果您不想自己动手， Guava提供了Primitives.wrap(Class) ，它接受基本类型并返回相应的包装器类型。

Answer 2

For integer:

int.class or the equivalent: Integer.TYPE;

Same for other primitive types

double.class or Double.TYPE
float.class or Float.TYPE
char.class or Character.TYPE
long.class or Long.TYPE
boolean.class Boolean.TYPE

Use it as follows:

Class intClass = int.class;

This then is a class that represents the primitive type int.

With that info, you simply write your own mapper: (You dont want to include an external lib for 8 lines of code)

public Class getClassForPrimitiveType(Class clazz) {
  if (clazz == int.class) return Integer.class;
  if (clazz == float.class) return Float.class;
  // TODO other primitives
}