CS 4773 Object Oriented Systems: Topic 12

CS 4773 Object Oriented Systems

Midterm Exam Solutions

Problem 1

   public class Point3 {
      private int x;
      private int y;
      private int z;

      public Point3(int x, int y, int z) {
         this.x = x;
         this.y = y;
         this.z = z;
      }

      public int get_x() {
         return x;
      }
    
      public int get_y() {
         return y;
      }
    
      public int get_z() {
         return z;
      }

      public void set(int x, int y, int z) {
         this.x = x;
         this.y = y;
         this.z = z;
      }
   }

Problem 2

5 points follow:
0: 0 -1
1: 1 0
2: 2 1
3: 3 2
4: 4 3
5 points follow:
0: 0 -1
1: 1 0
2: 2 1
3: 9 2
4: 4 3
5 points follow:
0: 0 -1
1: 9 2
2: 2 1
3: 9 2
4: 4 3
5 points follow:
0: 0 -1
1: 200 300
2: 2 1
3: 200 300
4: 4 3
5 points follow:
0: 0 -1
1: 500 700
2: 2 1
3: 500 700
4: 4 3

Problem 3

Key points:

The info_class should have a constructor
It should make a copy of the string (like the C program does) and not just copy the pointer
The constructor for info_class should be used in insert
Use the equals method to compare strings
You do not need a labeled break for delete
Output is formatted in the C version, so it should also be in the Java version.

class info_class {
   String name;
   int SSN;

   info_class(String name, int SSN) {
      this.name = new String(name);
      this.SSN = SSN;
   }
}

class information {
   info_class[] info;
   int info_size;
   int max_size;

   information(int max_size) {
      this.max_size = max_size;
      info = new info_class[max_size];
      info_size = 0;
   }

   int insert(String name, int SSN) {
      if (info_size == max_size) return -1;
      info[info_size] = new info_class(name,SSN);
      info_size++;
      return info_size;
   }

   info_class find_name(String name) {
      for (int i=0;i< info_size; i++)
         if (info[i].name.equals(name))
            return info[i];
      return null;
   }
 
   void delete(int SSN) {
      int i;
      for (i=0;i< info_size;i++)
         if (info[i].SSN == SSN) {
            info_size--;
            break;
         }
      for ( ; i< info_size; i++)
          info[i] = info[i+1];
   }
 
   void show() {
      String ssn;
      System.out.println("Size is "+info_size);
      for (int i=0;i< info_size;i++) {
         ssn = info[i].SSN + " ";
         while (ssn.length() <  13) ssn = " " + ssn;
         System.out.println(ssn+info[i].name);
      }  
   }
 
}

Open up a Java console and then click Here to run an applet that uses these classes. The output will appear in the Java console.

Documenting Java programs with javadoc

javadoc will create html files with documentation like the java online documentation.

All you need to do is to insert comments into your code in the right format.

Here is an example entry that is generated.

To have javadoc create documentation for a package:

Decide on a directory to contain your documentation.
It should be under your public_html
in that directory, make a directory called images and copy all of the files from /usr/local/courses/cs4773/spring97/javadoc/images to your directory.
Add the documentation to your code.
Run javadoc from the directory containing your package:
```
   javadoc -d destination_directory package_name
```
Put in a link to this in your course homepage to Package-package_name.html

Several html files will be generated.

AllNames.html: containing all public fields and methods
packages.html: containing all packages
tree.html: Containing a tree of objects
Package-package_name.html: containing a links to public packages
package_name.class_name.html: for each public class

Here is the javadoc documentation

Here is the JOTSA documentation created so far.

So far, a first pass has been made on the following:

JotsaAnimationObject
JotsaAnimationApplet (incomplete)
JotsaAnimationCollection