Fill in the following program at the three comment spots. Convert the user input

Question

Fill in the following program at the three comment spots. Convert the user input into a command line argument of the full path class name. Add the code in the getm() method for the loop to find all the get methods in the Class named cls. For our purpose, a get method would start with get, is not a void return, and has no arguments. Then add the code in the setm() method for the loop to find all the set methods in the Class named cls. For our purpose, a set method would start with set, is a void return, and has one argument.

For the getm() method, get all methods for the cls Class, loop through the methods and print all methods that are get methods - start with get, is not a void return, and has no arguments.

For the setm() method, get all methods for the cls Class, loop through the methods and print all methods that are set methods - start with set, is a void return, and has one argument.

For the void, check out the Void class and the TYPE data field. Try the program by inputting classes with a full path, such as: java.util.Date     javax.swing.JLabel    java.lang.reflect.Method. Save as ex173b.java and submit it.

/*
This program will let the user give a class name to find the
get and set Methods. Test with:
java.util.Date
javax.swing.JLabel
java.lang.reflect.Method
*/

package rtti17;
import java.io.*;
import java.lang.reflect.Method;

public class ex173
{
    public static void main(String[] args) throws IOException
    {
        String classname;
        Class x;
        BufferedReader br = new
            BufferedReader(new InputStreamReader(System.in));

        /* Convert this user input to a command line argument */

        System.out.print("Enter a full path class name: ");
        classname = br.readLine();
        try
        {
            x = Class.forName(classname);
            getm(x);
            System.out.println();
            setm(x);
        }
        catch(Exception ex)
        {
            ex.printStackTrace();
        }
    }

    public static void getm(Class cls)
    {
        int i;
        String methodname;
        Class rettype;
        Class[] paramtypes;
        Method[] ma;
        System.out.println("Listing get methods for " + cls);

        /* get all methods for the cls Class, loop through methods and
        print all methods that are get methods - start with get, is
        not a void return, and has no arguments
        */

    }

    public static void setm(Class cls)
    {
        int i;
        String methodname;
        Class rettype;
        Class[] paramtypes;
        Method[] ma;
        System.out.println("Listing set methods for " + cls);

        /* get all methods for the cls Class, loop through methods and
        print all methods that are set methods - start with set, is
        a void return, and has one argument
        */

    }
}

Explanation / Answer

import java.io.*;
import java.lang.reflect.Method;

public class ex173
{
public static void main(String[] args) throws IOException
{
String classname;
Class x;
  
if(args.length != 1) {
   throw new IllegalArgumentException("Only Class path must be given as command line argument.");
}
  
  
/* Convert this user input to a command line argument */
classname = args[0];
try
{
x = Class.forName(classname);
getm(x);
System.out.println();
setm(x);
}
catch(Exception ex)
{
ex.printStackTrace();
}
}

public static void getm(Class cls)
{
int i;
String methodname;
Class rettype;
Class[] paramtypes;
Method[] ma;
System.out.println("Listing get methods for " + cls);

/* get all methods for the cls Class, loop through methods and
print all methods that are get methods - start with get, is
not a void return, and has no arguments
*/
ma = cls.getMethods();
for(Method m: ma) {
   if(!m.getReturnType().equals(Void.TYPE) && m.getName().startsWith("get") && m.getParameterCount() == 0) {
       System.out.println(m.getName());
   }
}

}

public static void setm(Class cls)
{
int i;
String methodname;
Class rettype;
Class[] paramtypes;
Method[] ma;
System.out.println("Listing set methods for " + cls);

/* get all methods for the cls Class, loop through methods and
print all methods that are set methods - start with set, is
a void return, and has one argument
*/
ma = cls.getMethods();
for(Method m: ma) {
   if(m.getReturnType().equals(Void.TYPE) && m.getName().startsWith("set") && m.getParameterCount() == 1) {
       System.out.println(m.getName());
   }
}
}
}

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