Output for Printing

Java does provide printing using PrinterJob objects, but I am going to show you another option for printing
and viewing output using HTML formated files. If the end goal is to generate a printout then use File->Print
through the Internet browser's menu options.

In the following example we will create a HTML table containing information created and stored in a Java
runtime environment.

Here is the example:

import java.io.*;
import java.util.Vector;

class HTMLTableOutput {

  public static void main(String args[]) {
    try {
      HTMLTableOutput hTO=new HTMLTableOutput();

      HTMLTableOutput.ContactPerson cpObj=hTO.new ContactPerson("John", "012-345-6789", "john@fiction.org");
      HTMLTableOutput.ContactPerson cpObj2=hTO.new ContactPerson("Joe", "987-654-3210", "joe@fiction.org");
      HTMLTableOutput.ContactPerson cpObj3=hTO.new ContactPerson("Mary", "121-212-1212", "mary@fiction.org");

      Vector vecContacts=new Vector();

      vecContacts.addElement(cpObj);
      vecContacts.addElement(cpObj2);
      vecContacts.addElement(cpObj3);


      File newFile=null;

      int intCountFile=0;

//This loop makes sure that we don't overwrite an existing file.
      while(true) {
        newFile=new File("HTMLTableOutput"+intCountFile+".html");
        if(newFile.exists()) {
          ++intCountFile;
          continue;
        }

        break;
      }


      RandomAccessFile raf=new RandomAccessFile(newFile, "rw");

      raf.writeBytes("<html>");
      raf.write(13);
      raf.write(10);
      raf.writeBytes("<body>");
      raf.write(13);
      raf.write(10);

//Make the table have 3 columns and width be half the window size
      raf.writeBytes("<table cols='3' border='1' width='50%'>");
      raf.write(13);
      raf.write(10);


//Set the first column's width to 40% of the table width
      raf.writeBytes("<col style='width:40%'>");
      raf.write(13);
      raf.write(10);

//Set the second column's width to 30% of the table width
      raf.writeBytes("<col style='width:30%'>");
      raf.write(13);
      raf.write(10);

//Set the third column's width to 30% of the table width
      raf.writeBytes("<col style='width:30%'>");
      raf.write(13);
      raf.write(10);


//Output the table headers for each column
      raf.writeBytes("<tr><th>Name</th><th>Phone</th><th>Email</th></tr>");
      raf.write(13);
      raf.write(10);

      for(int i=0;i<vecContacts.size();i++) {
        HTMLTableOutput.ContactPerson nextContact=(HTMLTableOutput.ContactPerson)vecContacts.elementAt(i);

        raf.writeBytes("<tr>");

//Output the data for the first cell
        raf.writeBytes("<td>");
        raf.writeBytes(nextContact.getName());
        raf.writeBytes("</td>");

//Output the data for the second cell
        raf.writeBytes("<td>");
        raf.writeBytes(nextContact.getPhone());
        raf.writeBytes("</td>");

//Output the data for the third cell
        raf.writeBytes("<td>");
        raf.writeBytes(nextContact.getEmail());
        raf.writeBytes("</td>");

        raf.writeBytes("</tr>");

        raf.write(13);
        raf.write(10);
      }

      raf.writeBytes("</table>");
      raf.write(13);
      raf.write(10);

      raf.writeBytes("</body>");
      raf.write(13);
      raf.write(10);
      raf.writeBytes("</html>");
      raf.write(13);
      raf.write(10);

      raf.close();
    }
    catch(Exception ex) {
      ex.printStackTrace();
    }
  }

  class ContactPerson {
    String strName;
    String strPhone;
    String strEmail;

    ContactPerson(String strName, String strPhone, String strEmail) {
      this.strName=strName;
      this.strPhone=strPhone;
      this.strEmail=strEmail;
    }

    public String getName() {
      return strName;
    }

    public String getPhone() {
      return strPhone;
    }

    public String getEmail() {
      return strEmail;
    }
  }
}



After compiling and running the above source file there will be a file called "HTMLTableOutput.html" file.
Double click on the file to view the html file in your Internet browser. If you want to you can try printing
the file using the menu bar's File->Print option. The most important part of the html file is where the
table is constructed. In your situation, you will need to modify the number of columns in the table, the border
of the table, and the width of the table. Also, adjust the number of "th"s and "td"s to match your printing preferences.

The HTML language has many useful layout features that can aid in your printing situation, but it is beyond the
scope of these lessons to cover the full HTML language. However, there are plenty of informative HTML tutorials
on the Internet should you choose to explore the HTML language in farther depth.

In this lesson, you learned how to use RandomAccessFile to write out HTML format Strings to create a presentable
file for viewing data or printing data.