public class ClassMain {
    private Integer age;
    private String name;
    private List<String> alias;
    public static void main(String[] args) {
        ClassMain classMain = new ClassMain();
        System.out.println("classMain 这个变量的类型:" + classMain.getClass());
        Field[] declaredFields = classMain.getClass().getDeclaredFields();
        for (Field declaredField : declaredFields) {
            System.out.println(declaredField.getName() + ":" + declaredField.getType());
        }
    }
}
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public interface ParameterizedType extends Type {
   // 获取实际的参数类型
    Type[] getActualTypeArguments();
  // 获取原始的类型
    Type getRawType();
  // 针对内部类、返回其外层的类型
    Type getOwnerType();
}
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public class ClassMain {
    private Integer age;
    private String name;
    private List<String> alias;
    public static void main(String[] args) {
        ClassMain classMain = new ClassMain();
        System.out.println("classMain 这个变量的类型:" + classMain.getClass());
        Field[] declaredFields = classMain.getClass().getDeclaredFields();
        for (Field declaredField : declaredFields) {
            System.out.println(declaredField.getName() + ":" + declaredField.getGenericType());
        }
    }
}
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// java.lang.reflect.Field#getGenericType
public Type getGenericType() {
    if (getGenericSignature() != null)
        return getGenericInfo().getGenericType();
    else
        return getType();
}
public Class<?> getType() {
  return type;
}
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public class ClassMain {
    private Integer age;
    private String name;
    private List<String> alias;
    public static void main(String[] args) {
        ClassMain classMain = new ClassMain();
        System.out.println("classMain 这个变量的类型:" + classMain.getClass());
        Field[] declaredFields = classMain.getClass().getDeclaredFields();
        for (Field declaredField : declaredFields) {
            Type type = declaredField.getGenericType();
            if (type instanceof ParameterizedType) {
                ParameterizedType parameterizedType = (ParameterizedType) type;
                for (Type actualTypeArgument : parameterizedType.getActualTypeArguments()) {
                    System.out.println(declaredField.getName() + " getActualTypeArguments:" + actualTypeArgument);
                }
                System.out.println(declaredField.getName() + " getOwnerType:" + parameterizedType.getOwnerType());
                System.out.println(declaredField.getName() + " getRawType:" + parameterizedType.getRawType());
            } else if (type instanceof Class) {
                System.out.println(declaredField.getName() + ":" + type);
            }
        }
    }
}
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static class Holder<T> {
    private T data;
}
private Holder<String> holder;
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public class Msg<T> {
    private T data;
}
public class StringMsg extends Msg<String>{
}
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Type genericSuperclass = StringMsg.class.getGenericSuperclass();
if (genericSuperclass instanceof ParameterizedType) {
  ParameterizedType parameterizedType = (ParameterizedType) genericSuperclass;
  System.out.println(parameterizedType.getRawType());
  System.out.println(parameterizedType.getOwnerType());
  for (Type actualTypeArgument : parameterizedType.getActualTypeArguments()) {
    System.out.println(actualTypeArgument.getTypeName());
  }
}
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public class StringMsg extends Msg<String>{
    List<String> process(){
        System.out.println();
        return null;
    }
}
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Method[] declaredMethods = StringMsg.class.getDeclaredMethods();
        for (Method declaredMethod : declaredMethods) {
            Type genericReturnType = declaredMethod.getGenericReturnType();
            if (genericReturnType instanceof ParameterizedType) {
                System.out.println(((ParameterizedType) genericReturnType).getActualTypeArguments()[0]);
                System.out.println(((ParameterizedType) genericReturnType).getRawType());
            }
        }
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static class Holder<T extends String & Serializable> {
    private T data;
    public T getData() {
        return data;
    }
}
static class SonHolder<T extends String> extends Holder<T>{
}
 private static void typeVariable() throws NoSuchFieldException, NoSuchMethodException {
        Field data = Holder.class.getDeclaredField("data");
        Type genericType = data.getGenericType();
        if (genericType instanceof TypeVariable) {
            TypeVariable typeVariable = (TypeVariable) genericType;
            System.out.println(typeVariable.getName());
        }
        Method getData = Holder.class.getDeclaredMethod("getData");
        Type genericReturnType = getData.getGenericReturnType();
        if (genericReturnType instanceof TypeVariable) {
            TypeVariable typeVariable = (TypeVariable) genericReturnType;
            System.out.println(typeVariable.getName());
        }
        Type genericSuperclass = SonHolder.class.getGenericSuperclass();
        if (genericSuperclass instanceof ParameterizedType) {
            Type actualTypeArgument = ((ParameterizedType) genericSuperclass).getActualTypeArguments()[0];
            if (actualTypeArgument instanceof TypeVariable) {
                System.out.println(((TypeVariable) actualTypeArgument).getName());
                Type[] bounds = ((TypeVariable) actualTypeArgument).getBounds();
                System.out.println();
            }
        }
    }
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static class Holder<T extends String & Serializable> {
    private T data;
    List<?> list;
    public T getData() {
        return data;
    }
}
 private static void wildcardType() throws  Exception {
        Field list = Holder.class.getDeclaredField("list");
        Type genericType = list.getGenericType();
        if (genericType instanceof ParameterizedType) {
            Type[] actualTypeArguments = ((ParameterizedType) genericType).getActualTypeArguments();
            if (actualTypeArguments[0] instanceof WildcardType) {
                WildcardType wildcardTypes = (WildcardType) actualTypeArguments[0];
                System.out.println(wildcardTypes.getUpperBounds()[0].getTypeName());
            }
        }
    }
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/**
     * 含有泛型数组的才是GenericArrayType
     * @param pTypeArray GenericArrayType type :java.util.List<java.lang.String>[];
     * genericComponentType:java.util.List<java.lang.String>
     * @param vTypeArray  GenericArrayType type :T[];genericComponentType:T
     * @param list ParameterizedType type :java.util.List<java.lang.String>;
     * @param strings type :class [Ljava.lang.String;
     * @param test type :class [Lcom.wangji.demo.GenericArrayTypeTest;
     */
    public void testGenericArrayType(List<String>[] pTypeArray, T[] vTypeArray
    , List<String> list, String[] strings, GenericArrayTypeTest[] test) {
    }
/**
     * 1、getGenericComponentType
     * 返回泛型数组中元素的Type类型，即List<String>[] 中的 List<String>（ParameterizedTypeImpl）
     * 、T[] 中的T（TypeVariableImpl）；
     * 值得注意的是，无论是几维数组，getGenericComponentType()方法都只会脱去最右边的[]，返回剩下的值；
     */
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public class T1<T> {
}
public class T2<T> extends T1<List<T>> {
}
public class T3 extends T2<Map<String,Integer>> {
}
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