Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;

public class Main {
    /**
     * When {@code Type} initialized with a value of an object, its fully qualified class name
     * will be prefixed with this.
     *
     * @see {@link ReflectionUtils#getClassName(Type)}
     */
    private static final String TYPE_CLASS_NAME_PREFIX = "class ";
    private static final String TYPE_INTERFACE_NAME_PREFIX = "interface ";

    /**
     * Returns an array of {@code Type} objects representing the actual type
     * arguments to this object.
     * If the returned value is null, then this object represents a non-parameterized
     * object.
     *
     * @param object the {@code object} whose type arguments are needed.
     * @return an array of {@code Type} objects representing the actual type
     *       arguments to this object.
     *
     * @see {@link Class#getGenericSuperclass()}
     * @see {@link ParameterizedType#getActualTypeArguments()}
     */
    public static Type[] getParameterizedTypes(Object object) {
        Type superclassType = object.getClass().getGenericSuperclass();
        if (!ParameterizedType.class.isAssignableFrom(superclassType.getClass())) {
            return null;
        }

        return ((ParameterizedType) superclassType).getActualTypeArguments();
    }

    /**
     * Returns the {@code Class} object associated with the given {@link Type}
     * depending on its fully qualified name.
     *
     * @param type the {@code Type} whose {@code Class} is needed.
     * @return the {@code Class} object for the class with the specified name.
     *
     * @throws ClassNotFoundException if the class cannot be located.
     *
     * @see {@link ReflectionUtils#getClassName(Type)}
     */
    public static Class<?> getClass(Type type) throws ClassNotFoundException {
        String className = getClassName(type);
        if (className == null || className.isEmpty()) {
            return null;
        }
        return Class.forName(className);
    }

    /**
     * {@link Type#toString()} value is the fully qualified class name prefixed
     * with {@link ReflectionUtils#TYPE_NAME_PREFIX}. This method will substring it, for it to be eligible
     * for {@link Class#forName(String)}.
     *
     * @param type the {@code Type} value whose class name is needed.
     * @return {@code String} class name of the invoked {@code type}.
     *
     * @see {@link ReflectionUtils#getClass()}
     */
    public static String getClassName(Type type) {
        if (type == null) {
            return "";
        }
        String className = type.toString();
        if (className.startsWith(TYPE_CLASS_NAME_PREFIX)) {
            className = className.substring(TYPE_CLASS_NAME_PREFIX.length());
        } else if (className.startsWith(TYPE_INTERFACE_NAME_PREFIX)) {
            className = className.substring(TYPE_INTERFACE_NAME_PREFIX.length());
        }
        return className;
    }
}