ClassReflector

/*
 * Roberto Burgos
 * CS211S
 * 11/19/2012
 * ClassReflection.java
 *
 * See Java doc.
 */
package com.rburgosnavas.jr.classreflector;

import java.lang.reflect.*;
import java.util.ArrayList;

/**
 * <p>
 * ClassReflector class is a Java class inspector that gets information about
 * any class. The name of the class is passed as a String. Several methods are
 * offered to get specific information about the class, for example a list of
 * all constructors, all public, private, or protected methods, etc.
 * </p>
 * <p>
 * For example:
 * <code>ClassReflector cr = new ClassReflector("java.lang.String")</code>
 * </p>
 * @author Roberto Burgos
 * @version 1
 */
public class ClassReflector
{

    private Class<?> c;
    private int numInterface, numConstructors, numMethods, numFields;

    /**
     * Constructor for ClassReflector which takes a String of the name of
     * the class that we need to get data from.
     * @param className String for the name of the class.
     */
    public ClassReflector(String className)
    {
        try
        {
            c = Class.forName(className);
            numInterface = c.getInterfaces().length;
            numConstructors = c.getDeclaredConstructors().length;
            numMethods = c.getDeclaredMethods().length;
            numFields = c.getDeclaredFields().length;
        }
        catch (ClassNotFoundException e)
        {
            System.err.println("Class not found.");
            System.exit(0);
        }
    }

    /**
     * Gets the name of the class.
     * @return The name of the class as a string
     */
    public String getClassName()
    {
        return c.getName();
    }

    /**
     * Gets the name of the superclass of the class in question
     * @return The name of the superclass as a String
     */
    public String getSuperclassName()
    {
        return c.getSuperclass().getName();
    }

    /**
     * Gets a list of all the interfaces implemented by the class in question.
     * @return An Object array of the list of interfaces.
     */
    public Object[] getInterfaces()
    {
        ArrayList<String> interfaces = new ArrayList<>();
        for (int i = 0; i < numInterface; i++)
        {
            interfaces.add(c.getInterfaces()[i].getName());
        }
        return interfaces.toArray();
    }

    /**
     * Gets all the constructors of the class in question.
     * @return An Object array of the list of all constructors.
     */
    public Object[] getAllConstructors()
    {
        ArrayList<String> constr = new ArrayList<>();
        for (int i = 0; i < numConstructors; i++)
        {
            constr.add(c.getDeclaredConstructors()[i].toString());
        }
        return constr.toArray();
    }

    /**
     * Gets all public constructors of the class in question.
     * @return An Object array of the list of all public constructors.
     */
    public Object[] getPublicConstructors()
    {
        ArrayList<String> constr = new ArrayList<>();
        for (int i = 0; i < numConstructors; i++)
        {
            if (Modifier.isPublic(
                    c.getDeclaredConstructors()[i].getModifiers()))
            {
                constr.add(c.getDeclaredConstructors()[i].toString());
            }
        }
        return constr.toArray();
    }

    /**
     * Gets all private constructors of the class in question.
     * @return An Object array of the list of all private constructors.
     */
    public Object[] getPrivateConstructors()
    {
        ArrayList<String> constr = new ArrayList<>();
        for (int i = 0; i < numConstructors; i++)
        {
            if (Modifier.isPrivate(
                    c.getDeclaredConstructors()[i].getModifiers()))
            {
                constr.add(c.getDeclaredConstructors()[i].toString());
            }
        }
        return constr.toArray();
    }

    /**
     * Gets all protected constructors of the class in question.
     * @return An Object array of the list of all protected constructors.
     */
    public Object[] getProtectedConstructors()
    {
        ArrayList<String> constr = new ArrayList<>();
        for (int i = 0; i < numConstructors; i++)
        {
            if (Modifier.isProtected(
                    c.getDeclaredConstructors()[i].getModifiers()))
            {
                constr.add(c.getDeclaredConstructors()[i].toString());
            }
        }
        return constr.toArray();
    }

    /**
     * Gets all methods of the class in question.
     * @return An Object array of the list of all methods.
     */
    public Object[] getAllMethods()
    {
        ArrayList<String> methods = new ArrayList<>();
        for (int i = 0; i < numMethods; i++)
        {
            methods.add(c.getDeclaredMethods()[i].toString());
        }
        return methods.toArray();
    }

    /**
     * Gets all public methods of the class in question.
     * @return An Object array of the list of all public methods.
     */
    public Object[] getPublicMethods()
    {
        ArrayList<String> methods = new ArrayList<>();
        for (int i = 0; i < numMethods; i++)
        {
            if (Modifier.isPublic(c.getDeclaredMethods()[i].getModifiers()))
            {
                methods.add(c.getDeclaredMethods()[i].toString());
            }
        }
        return methods.toArray();
    }

    /**
     * Gets all private methods of the class in question.
     * @return An Object array of the list of all private methods.
     */
    public Object[] getPrivateMethods()
    {
        ArrayList<String> methods = new ArrayList<>();
        for (int i = 0; i < numMethods; i++)
        {
            if (Modifier.isPrivate(c.getDeclaredMethods()[i].getModifiers()))
            {
                methods.add(c.getDeclaredMethods()[i].toString());
            }
        }
        return methods.toArray();
    }

    /**
     * Gets all protected methods of the class in question.
     * @return An Object array of the list of all protected methods.
     */
    public Object[] getProtectedMethods()
    {
        ArrayList<String> methods = new ArrayList<>();
        for (int i = 0; i < numMethods; i++)
        {
            if (Modifier.isProtected(c.getDeclaredMethods()[i].getModifiers()))
            {
                methods.add(c.getDeclaredMethods()[i].toString());
            }
        }
        return methods.toArray();
    }

    /**
     * Gets all fields of the class in question.
     * @return An Object array of the list of all fields.
     */
    public Object[] getAllFields()
    {
        ArrayList<String> fields = new ArrayList<>();
        for (int i = 0; i < numFields; i++)
        {
            fields.add(c.getDeclaredFields()[i].toString());
        }
        return fields.toArray();
    }

    /**
     * Gets all public fields of the class in question.
     * @return An Object array of the list of all public fields.
     */
    public Object[] getPublicFields()
    {
        ArrayList<String> fields = new ArrayList<>();
        for (int i = 0; i < numFields; i++)
        {
            if (Modifier.isPublic(c.getDeclaredFields()[i].getModifiers()))
            {
                fields.add(c.getDeclaredFields()[i].toString());
            }
        }
        return fields.toArray();
    }

    /**
     * Gets all private fields of the class in question.
     * @return An Object array of the list of all private fields.
     */
    public Object[] getPrivateFields()
    {
        ArrayList<String> fields = new ArrayList<>();
        for (int i = 0; i < numFields; i++)
        {
            if (Modifier.isPrivate(c.getDeclaredFields()[i].getModifiers()))
            {
                fields.add(c.getDeclaredFields()[i].toString());
            }
        }
        return fields.toArray();
    }

    /**
     * Gets all protected fields of the class in question.
     * @return An Object array of the list of all protected fields.
     */
    public Object[] getProtectedFields()
    {
        ArrayList<String> fields = new ArrayList<>();
        for (int i = 0; i < numFields; i++)
        {
            if (Modifier.isProtected(c.getDeclaredFields()[i].getModifiers()))
            {
                fields.add(c.getDeclaredFields()[i].toString());
            }
        }
        return fields.toArray();
    }

}