Getting Params from JSP to Action Class? (Struts 2)

[Daniel Foley]

Hey, these forums have been great so far but I'm hoping to get some more help.

I have a jsp page that prints out the results from a DB as a link (navigation)

<%-- 				<s:if test='fList.size()>0'> --%>
					<s:iterator value = 'fList'>
							<li><a href='<s:url action="disp3" ><s:param name="contId" value="%{contId}" /></s:url>'><s:property value="country" /></a>
					</s:iterator>
<%-- 				</s:if> --%>

which generates a link like:
http://localhost:8080/StrutsBoard/disp3.action?contId=0 "General"
http://localhost:8080/StrutsBoard/disp3.action?contId=1 "Africa"
http://localhost:8080/StrutsBoard/disp3.action?contId=2 "Antarctica"
etc etc

disp3 is mapped in my struts.xml to go to this method in my action class:

public String display()
	{
		int temp = getForumId();
		
		fList=Forum.GetAll();
		tList=Threads.GetSome(temp);
		return "listed";
	}

No matter what I do, I cannot figure out what connection I need to make to get that contId from the link and pass it to the Threads.GetSome() method.

Once it passes the value, the end results work out fine (I've tested it be hardcoding)

here's the full pages if that'll help:
ThreadAction.java

package ActionClasses;

import java.util.ArrayList;

// import java.util.List;

import BOLClasses.Forum;
import BOLClasses.Login;
import BOLClasses.Threads;

public class ThreadAction {

	int postId;
	int forumId;
	String postForum;
	String postUser;
	String postTime;
	String postSubject;
	String postMessage;

	public ArrayList<Forum> fList = new ArrayList<Forum>();
	public ArrayList<Threads> tList = new ArrayList<Threads>();
	
	public int getPostId() {
		return postId;
	}
	public void setPostId(int postId) {
		this.postId = postId;
	}
	public int getForumId() {
		return forumId;
	}
	public void setForumId(int forumID) {
		this.forumId = forumID;
	}
	public String getPostForum() {
		return postForum;
	}
	public void setPostForum(String postForum) {
		this.postForum = postForum;
	}
	public String getPostUser() {
		return postUser;
	}
	public void setPostUser(String postUser) {
		this.postUser = postUser;
	}
	public String getPostTime() {
		return postTime;
	}
	public void setPostTime(String postTime) {
		this.postTime = postTime;
	}
	public String getPostSubject() {
		return postSubject;
	}
	public void setPostSubject(String postSubject) {
		this.postSubject = postSubject;
	}
	public String getPostMessage() {
		return postMessage;
	}
	public void setPostMessage(String postMessage) {
		this.postMessage = postMessage;
	}
	public boolean editMode = false;
	
	public boolean isEditMode() {
		return editMode;
	}
	public void setEditMode(boolean editMode) {
		this.editMode = editMode;
	}

	public String execute() throws Exception
	{		
		setPostId(postId);
		setPostUser(Login.UserName);
		setPostTime(postTime);
		setPostSubject(postSubject);
		setPostMessage(postMessage);
		setForumId(forumId);
		setPostForum(postForum);

		System.out.println("Execute: " + postId + " " + postUser + " Login: " + Login.UserName);
		
		return "set";
	}
	
	public String display()
	{
		int temp = getForumId();
		
		fList=Forum.GetAll();
		tList=Threads.GetSome(temp);
		return "listed";
	}
	
	public String Insert()
	{
		if (Login.UserName == null){
			return "userfail";
		}
		else{
			Threads t = new Threads ();
		
			t.setPostId(postId);
			t.setPostUser(postUser);
			t.setPostTime(postTime);
			t.setPostSubject(postSubject);
			t.setPostMessage(postMessage);
			t.setPostForum(forumId);
			
			t.insert();
			tList=Threads.GetAll();
			
			editMode=true;
			
			return "saved";
		}
	}
	
	public String Update()
	{
		System.out.println("Here I am 4 - " + postUser);
		
		if (Login.UserName == null){
			System.out.println("User: " + Login.UserName);
			return "userfail";
		}
		else{
			Threads t = new Threads ();
			
			editMode=true;
			
			t.setPostId(postId);
			t.setPostUser(postUser);
			t.setPostTime(postTime);
			t.setPostSubject(postSubject);
			t.setPostMessage(postMessage);
			t.setPostForum(forumId);
			
			t.update();
			tList=Threads.GetAll();
			editMode=false;
	
			return "edited";
		}
	}
	
	public String Delete()
	{
		Threads t = new Threads ();

		t.setPostId(postId);
		
		t.delete();
		tList=Threads.GetAll();
		return "deleted";		
	}
}

Threads.java

package BOLClasses;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

public class Threads {

	int postId;
	int forumId;
	String postForum;
	String postUser;
	String postTime;
	String postSubject;
	String postMessage;
	
	public int getPostId() {
		return postId;
	}
	public void setPostId(int postId) {
		this.postId = postId;
	}
	public int getForumId() {
		return forumId;
	}
	public void setForumId(int forumID) {
		forumId = forumID;
		System.out.println("Thread - setForumId ID " + forumID + " now " + forumId);
	}
	public String getPostForum() {
		return postForum;
	}
	public String setPostForum(int forumNum) {

		System.out.println("Thread sPF - ID " + forumNum);
		ArrayList<Threads> DbList = new ArrayList<Threads>();
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);

			String sql = String.format("Select contId, country from forumDB WHERE contId = '%d'", forumNum);
			Statement st = con.createStatement();

			ResultSet rs = st.executeQuery(sql);
			while (rs.next())
			{
				Threads t = new Threads();
				t.forumId = rs.getInt("contId");
				setForumId(t.forumId);
				t.postForum = rs.getString("country");
				this.postForum = t.postForum;
				
				System.out.println("Thread sPF - While " + t.forumId + " " + t.postForum);

				DbList.add(t);
			}
			rs.close();
		} catch (Exception e)
		{
			System.out.println("Thread sPF - Exception " + forumId + " " + postForum);
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return postForum;
	}
	
	public String getPostUser() {
		return postUser;
	}
	public void setPostUser(String postUser) {
		this.postUser = Login.UserName;
		System.out.println("THSet: " + postUser + " Login: " + Login.UserName);
	}
	
	public String getPostTime() {
		return postTime;
	}
	public void setPostTime(String postTime) {
		Date dateNow = new Date ();
		SimpleDateFormat dateFormat = new SimpleDateFormat("MM-dd-yyyy-hh:mm:ss");
        StringBuilder strDate = new StringBuilder( dateFormat.format( dateNow ) );
        postTime = strDate.toString();
        
		this.postTime = postTime;
	}
	public String getPostSubject() {
		return postSubject;
	}
	public void setPostSubject(String postSubject) {
		if (!postSubject.isEmpty()){
			postSubject = postSubject.replace("'", "''");
		}
		this.postSubject = postSubject;
	}
	public String getPostMessage() {
		return postMessage;
	}
	public void setPostMessage(String postMessage) {
		if (!postMessage.isEmpty()){
			postMessage = postMessage.replace("'", "''");
		}
		this.postMessage = postMessage;
	}
	
	static public ArrayList<Threads> GetAll()
	{
		ArrayList<Threads> DbList = new ArrayList<Threads>();
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);

			String sql = String.format("SELECT postId, postUser, postTime, postSubject, postMessage, postForum from postDiscussion");
			Statement st = con.createStatement();
			
			ResultSet rs = st.executeQuery(sql);
			while (rs.next())
			{ 
				Threads t = new Threads();

				t.postId = rs.getInt("postId");
				t.postUser = rs.getString("postUser");
				t.postTime = rs.getString("postTime");
				t.postSubject = rs.getString("postSubject");
				t.postMessage = rs.getString("postMessage");
				t.forumId = rs.getInt("postForum");
				t.postForum = t.setPostForum(t.forumId);

				DbList.add(t);
			}
			rs.close();
		} catch (Exception e)
		{
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		// System.out.println(DbList);
		return DbList;
	}
	
	static public ArrayList<Threads> GetSome(int forumNum)
	{
		System.out.println("Threads GetSome - ForumNum " + forumNum);
		ArrayList<Threads> DbList = new ArrayList<Threads>();
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);

			String sql = String.format("SELECT postId, postUser, postTime, postSubject, postMessage, postForum from postDiscussion WHERE postForum = '%d' ", forumNum);
			Statement st = con.createStatement();
			
			ResultSet rs = st.executeQuery(sql);
			while (rs.next())
			{ 
				Threads t = new Threads();

				t.postId = rs.getInt("postId");
				t.postUser = rs.getString("postUser");
				t.postTime = rs.getString("postTime");
				t.postSubject = rs.getString("postSubject");
				t.postMessage = rs.getString("postMessage");
				t.forumId = rs.getInt("postForum");
				t.postForum = t.setPostForum(t.forumId);
				
				System.out.println("Threads GetSome - forumId " + t.forumId + " postForum "+ t.postForum);

				DbList.add(t);
			}
			rs.close();
		} catch (Exception e)
		{
			System.out.println("Threads GetSome - Exception " + forumNum);
			// TODO Auto-generated catch block
			// e.printStackTrace();
		}
		// System.out.println(DbList);
		return DbList;
	}

	public void insert()
	{
		int memBuff = 0;
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);
			
			String sql = String.format("SELECT postId from postDiscussion");
			Statement st = con.createStatement();
			
			ResultSet rs = st.executeQuery(sql);
			
			while (rs.next()) {
				this.postId = rs.getInt("postId");
				if(postId == memBuff){
					System.out.println("postId " + postId + " exists already.");
					//++MemberID;
					//memBuff = MemberID;
					++memBuff;
					System.out.println("Trying " + memBuff);
				}
			}
			postId = memBuff;

			System.out.println("insert: " + postId + " "  + postUser + " " + postTime + " " + postSubject + " " + postMessage + " " + forumId);
			sql = String.format("INSERT INTO postDiscussion VALUES('%d', '%s', '%s', '%s', '%s', '%d')", postId, postUser, postTime, postSubject, postMessage, forumId);
			st = con.createStatement();
			st.executeUpdate(sql);
			
		} catch (Exception e)
		{	
			e.printStackTrace();
		}
	}
	
	public void update()
	{
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);

			// System.out.println("update: " + postId + " "  + postUser + " " + postTime + " " + postSubject + " " + postMessage);
			String sql = String.format("UPDATE postDiscussion SET postSubject = '%s', postMessage='%s' WHERE postId = '%d' ", postSubject, postMessage, postId);
			Statement st = con.createStatement();

			st.executeUpdate(sql);
		} catch (Exception e)
		{
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	public void delete()
	{
		try
		{
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
			String connectionUrl = "jdbc:sqlserver://127.0.0.1;database=Forums;integratedSecurity=false;User=admin;Password=adminPass;";
			Connection con = DriverManager.getConnection(connectionUrl);

			String sql = String.format("DELETE FROM postDiscussion WHERE postId = '%d' ",postId);
			Statement st = con.createStatement();

			st.executeUpdate(sql);
		} catch (Exception e)
		{
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

[Jinal Prakas Shah]

Hi Daniel try this

<s:url action="disp3" var="urlTag">
    <s:param name="contId">%{contId}</s:param>
</s:url>
<a href="<s:property value="#urlTag" />"><s:property value="country" /></a>

I think this should work.

[Daniel Foley]

That seems to do about the same, the navigation links display fine, but I'm still not getting the value in the Action Class.

It ends up getting null or 0 every time instead of what contId is passing.

Is there a getter/setter I need to setup on ThreadAction.java?

[Jinal Prakas Shah]

Yes you will need getter/setters for flist and what is contId? where are you declaring it?

[Daniel Foley]

contId is an int from the table forumDB, set to the int forumId (in the "public String setPostForum(int forumNum)" method)

And just in case anyone's curious, all of my System.out.println are just for debugging purposes.

[Jinal Prakas Shah]

Do 1 thing separtely in that iteration of your's try to print the value of contId using <s:property value="contId"/> just to check whether you are able to access the variable or not.

[Daniel Foley]

doing <s:property value="contId"/>

Yes, the contId does list it out properly from the DB, I even just changed one int in the table from 8 to 9 to be sure and it works fine.

[Jinal Prakas Shah]

so instead of %{contId} use #contId.

[Jinal Prakas Shah]

can you put the <s:property> tag in between <s:param> tag

[Daniel Foley]

<s:url action="disp3" var="urlTag">
	<s:param name="contId">#contId</s:param>
</s:url>
    	<li><a href="<s:property value="#urlTag" />"><s:property value="country" /></a>

?

That doesn't work, it makes the link
http://localhost:8080/StrutsBoard/disp3.action?contId=#contId

where as before the contId was actually the correct int.

[Jinal Prakas Shah]

Try this
<s:param name="contId" value="#contId"/>

This should work

[Daniel Foley]

<s:url action="disp3" var="urlTag"><s:param name="contId">	<s:property value="contId"/></s:param></s:url>
	<li><a href="<s:property value="#urlTag" />"><s:property value="country" /></a>

works fine

[Jinal Prakas Shah]

cool. Is that all or you need more help?

[Daniel Foley]

Well that part was already working

But those values are not being read into the ThreadAction.java file

public String display()  
    {  
        int temp = getForumId();  
          
        fList=Forum.GetAll();  
        tList=Threads.GetSome(temp);  
        return "listed";  
    }

My links generate dynamically awesomely, but that int temp (ThreadAction.java) needs to somehow get the contId (jsp). That's where I'm having problems.

[Jinal Prakas Shah]

This is what you need to do
1. Make your Action implement the ParameterAware interface.

2. Define a class variable for parameters Map:
private Map parameters;

3. Create getter and setter methods for the above defined parameters Map.

4. Calling getParameters() gives you access to the request parameters through the above defined Map.

5. To make things simple, you can create a getParameterValue() method to return value of a request parameter by its name:

public String getParameterValue(String param) {
Object varr = getParameters().get(param);
if (varr == null) return null;
return ((String[]) varr)[0];
}

Regards

[Jinal Prakas Shah]

You need to extend extends ActionSupport for your Struts Action class.

[Daniel Foley]

Ok, just a tiny bit lost, so that would go like so:

public class ThreadAction extends ActionSupport implements ParameterAware{
	
	private Map parameters;
	
	public String getParameterValue(String param) {
		Object varr = getParameters().get(param);
		if (varr == null) return null;
		return ((String[]) varr)[0];
	} 
	
	public Map getParameters() {
		return parameters;
	}
	public void setParameters(Map parameters) {
		this.parameters = parameters;
	}

so I would just make it getParameters().get(contId)?

[Jinal Prakas Shah]

yaah you can

[Jinal Prakas Shah]

but remember it will give you an object and not String when you do so.

[Daniel Foley]

I'm lost now... still not sure how that is looking for the param from the jsp

Also, the only value being passed via that param will be an int so can I change around the String in there to int?

[Jinal Prakas Shah]

Behind the scene it is accessing the HttpServletRequest object and getting the parameters from the URL for you as a name value fashion in the Map class object.