(JAVA Servlets using tomcat) Using a form for text input (name = 'query') and submit, modify the GuestBook servlet so that it has a "search" function. For example, typing a word or letter and clicking the submit button would return any result with that word/letter in the Name or Message column as a table. The following is the code that is to be added onto, which works as an ordinary guestbook, all that needs to be done is a modification of Guestbook.java: Guestbook.java package cs320.servlet;

import java.io.IOException; import java.io.PrintWriter; import java.util.ArrayList; import java.util.List;

import javax.servlet.ServletConfig; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;

import cs320.model.GuestBookEntry;

@WebServlet(urlPatterns = "/GuestBook", loadOnStartup = 2) public class GuestBook extends HttpServlet {

private static final long serialVersionUID = 1L;

public GuestBook() { super(); }

public void init( ServletConfig config ) throws ServletException { super.init( config );

// create some test data for display List entries = new ArrayList(); entries.add( new GuestBookEntry( 1, "john", "hello" ) ); entries.add( new GuestBookEntry( 2, "joe", "hi" ) );

// stored the data somewhere that can be accessed by this servlet // and other servlets. getServletContext().setAttribute( "entries", entries ); }

@SuppressWarnings("unchecked") protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { // get the data List entries = (List) getServletContext().getAttribute( "entries" );

// display it response.setContentType( "text/html" ); PrintWriter out = response.getWriter(); out.println( "

Guest Book

" );

out.println( "" ); out.println( "" ); for( GuestBookEntry entry : entries ) { out.println( "" ); } out.println( "

Id	Name	Message
" + entry.getId() + "	" + entry.getName() + "	" + entry.getMessage() + "	Edit Delete

" );

out.println( "

Add Comment

" );

out.println( "" ); }

protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { doGet( request, response ); }

}

GuestBookEntry.java

package cs320.model; public class GuestBookEntry { Integer id; String name; String message; public GuestBookEntry( Integer id, String name, String message ) { this.id = id; this.name = name; this.message = message; } public Integer getId() { return id; } public void setId( Integer id ) { this.id = id; } public String getName() { return name; } public void setName( String name ) { this.name = name; } public String getMessage() { return message; } public void setMessage( String message ) { this.message = message; } } 

AddComment.java

package cs320.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.List; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cs320.model.GuestBookEntry; @WebServlet("/AddComment") public class AddComment extends HttpServlet { private static final long serialVersionUID = 1L; int idSeed = 100; public AddComment() { super(); } protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { // display form response.setContentType( "text/html" ); PrintWriter out = response.getWriter(); out.println( " 

Add Comment" ); out.println( "

" ); out.println( "Name: " ); out.println( " " ); out.println( " " ); out.println( "

" ); out.println( "" ); } @SuppressWarnings("unchecked") protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { // get the user input String name = request.getParameter( "name" ); String message = request.getParameter( "message" ); // create a new guest book entry GuestBookEntry entry = new GuestBookEntry( idSeed++, name, message ); // add the new entry to the guest book List entries = (List) getServletContext().getAttribute( "entries" ); entries.add( entry ); // send the user back to the guest book page response.sendRedirect( "GuestBook" ); } }

EditComment.java

package cs320.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.List; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cs320.model.GuestBookEntry; @WebServlet("/EditComment") public class EditComment extends HttpServlet { private static final long serialVersionUID = 1L; public EditComment() { super(); } /** * Given an id, retrieve the GuestBookEntry. */ @SuppressWarnings("unchecked") private GuestBookEntry getEntry( Integer id ) { List entries = (List) getServletContext().getAttribute( "entries" ); for( GuestBookEntry entry : entries ) if( entry.getId().equals( id ) ) return entry; return null; } protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { // get the entry to be edited Integer id = Integer.valueOf( request.getParameter( "id" ) ); GuestBookEntry entry = getEntry( id ); // form display response.setContentType( "text/html" ); PrintWriter out = response.getWriter(); out.println( "Edit Comment" ); out.println( "

" ); out.println( "Name: " ); out.println( "" + entry.getMessage() + " " ); // hidden form field out.println( " " ); out.println( " " ); out.println( "

" ); out.println( "" ); } protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { // get the entry to be edited Integer id = Integer.valueOf( request.getParameter( "id" ) ); GuestBookEntry entry = getEntry( id ); // change the entry based on user input entry.setName( request.getParameter( "name" ) ); entry.setMessage( request.getParameter( "message" ) ); // send the user back to the guest book page response.sendRedirect( "GuestBook" ); } }

DeleteComment.java

package cs320.servlet; import java.io.IOException; import java.util.List; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import cs320.model.GuestBookEntry; @WebServlet("/DeleteComment") public class DeleteComment extends HttpServlet { private static final long serialVersionUID = 1L; public DeleteComment() { super(); } @SuppressWarnings("unchecked") protected void doGet( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { Integer id = Integer.valueOf( request.getParameter( "id" ) ); List entries = (List) getServletContext().getAttribute( "entries" ); for( GuestBookEntry entry : entries ) if( entry.getId().equals( id ) ) { entries.remove( entry ); break; } response.sendRedirect( "GuestBook" ); } protected void doPost( HttpServletRequest request, HttpServletResponse response ) throws ServletException, IOException { doGet( request, response ); } }