[2 days left] What’s wrong with your cloud strategy? Learn why multicloud solutions matter with Nimble Storage.Register Now

x
?
Solved

java programming

Posted on 2004-10-01
15
Medium Priority
?
189 Views
Last Modified: 2010-03-31
Class cc=Class.forName(className);
Field[] ff=cc.getDeclaredFields();

for(int i=0;i<ff.length;i++)
         {

                    Class type =ff[i].getType();
                    
                    if(type.isPrimitive()==false)
                    {
                      Class treeset =Class.forName(ff[i]);
                            }
 }
}
Iam getting error from the above code,how to retrieve non-primitive field ,class and store in a class treeset?
0
Comment
Question by:sraveend
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 6
  • 6
  • 2
  • +1
15 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 12204400
You should be OK

            String className = "java.lang.String";
            Class cc = Class.forName(className);
            Field[] ff = cc.getDeclaredFields();

            for (int i = 0; i < ff.length; i++) {

                  Class type = ff[i].getType();

                  if (type.isPrimitive() == false) {
                        //Class treeset = Class.forName(ff[i]);
                        System.out.println("Found " + type);
                  }
            }

0
 
LVL 92

Expert Comment

by:objects
ID: 12204415
Class.forName() expects a String, and not a Field instance.
and you don't need to call Class.forName() as you alreay have the Class instance 'type'.
0
 
LVL 30

Accepted Solution

by:
Mayank S earned 1600 total points
ID: 12206511
>> Class treeset =Class.forName(ff[i]);

I think you want to do:

TreeSet trList = new TreeSet () ;
Class cc = Class.forName ( className ) ;
Field[] ff = cc.getDeclaredFields () ;

for ( int i = 0 ; i < ff.length ; i ++)
{
  Class type = ff[i].getType () ;

  if ( type.isPrimitive () == false )
    trList.add ( ff[i] ) ; // end if

} // end for
0
Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

 
LVL 30

Expert Comment

by:Mayank S
ID: 12206514
You can then display them using:

Iterator itTreeItems = trList.iterator () ;

while ( itTreeItems.hasNext () )
{
  Field f = ( Field ) itTreeItems.next () ;
  System.out.println ( f.getName () ) ;

} // end while
0
 

Author Comment

by:sraveend
ID: 12206849
Is there any option to find a package from a field type?
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 12206855
The class name of the field will give the package
0
 

Author Comment

by:sraveend
ID: 12206860
Can we declare a field as a package?
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 12206884
Not sure what you mean by that
0
 

Author Comment

by:sraveend
ID: 12206904
U've given class name of the field gives the package name,i just want an example
0
 
LVL 86

Assisted Solution

by:CEHJ
CEHJ earned 400 total points
ID: 12206919
while ( itTreeItems.hasNext () )
{
  Field f = ( Field ) itTreeItems.next () ;
  System.out.println ( f.getName () ) ;
  String fqName = f.getDeclaringClass().toString();
  String packageName = fqName.substring(0, fqName.lastIndexOf("."));
  System.out.println (packageName) ;
} // end while
0
 

Author Comment

by:sraveend
ID: 12207000
Class cc=Class.forName(className);
Field[] ff=cc.getDeclaredFields();

for(int i=0;i<ff.length;i++)
         {

                    Class type =ff[i].getType();


                    if(type.isPrimitive()==false)
                    {
                    String fqName = type.toString();
                    int x=fqName.length();
                      String cName = fqName.substring(fqName.lastIndexOf(".")+1,x);
                      System.out.println("class name="+cName);

Class tset=Class.forName(TreeSet);
Field[] f=tset.set(String,cName);

                      String packageName = fqName.substring(0, fqName.lastIndexOf("."));
                      System.out.println("packagename="+packageName);

                           }
 }

Iam getting correct result for cName&packageName
But how to store class name (cName) in a class TreeSet.
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 12207044
someSet.add(cName);
0
 

Author Comment

by:sraveend
ID: 12207088
Class cc=Class.forName(className);
Field[] ff=cc.getDeclaredFields();
TreeSet trList = new TreeSet();
for(int i=0;i<ff.length;i++)
         {

                    Class type =ff[i].getType();


                    if(type.isPrimitive()==false)
                    {
                    String fqName = type.toString();
                    int x=fqName.length();
                      String cName = fqName.substring(fqName.lastIndexOf(".")+1,x);
                      System.out.println("class name="+cName);

//Class tset=trList.class;
trList.add(cName);

                      String packageName = fqName.substring(0, fqName.lastIndexOf("."));
                      System.out.println("packagename="+packageName);

                           }
 }
Iam getting error in add?
0
 

Author Comment

by:sraveend
ID: 12208738
AM sorry, i've corrected my error.....
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 12208852
8-)
0

Featured Post

Important Lessons on Recovering from Petya

In their most recent webinar, Skyport Systems explores ways to isolate and protect critical databases to keep the core of your company safe from harm.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Java contains several comparison operators (e.g., <, <=, >, >=, ==, !=) that allow you to compare primitive values. However, these operators cannot be used to compare the contents of objects. Interface Comparable is used to allow objects of a cl…
Java had always been an easily readable and understandable language.  Some relatively recent changes in the language seem to be changing this pretty fast, and anyone that had not seen any Java code for the last 5 years will possibly have issues unde…
Viewers learn about the “for” loop and how it works in Java. By comparing it to the while loop learned before, viewers can make the transition easily. You will learn about the formatting of the for loop as we write a program that prints even numbers…
Viewers will learn one way to get user input in Java. Introduce the Scanner object: Declare the variable that stores the user input: An example prompting the user for input: Methods you need to invoke in order to properly get  user input:
Suggested Courses

649 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question