Custom taglib access the variable of jsp in the tag class
Hi guys:
I have a question about taglib.the scenario below
there are a set of tag,they all need to access a variable that declare in the jsp.yes ,I can use the approach like this,
first I declare a variable
<%!String variable="test";%>
then pass the value
<myTag:hello att="<%=variable%>"/>,but I think that's stupid,because all tags access the same variable.why not get the variable in tag class?
for example
public int doStartTag() {
String variable=;//get the variable at here
I mean,I want to get the variable's value in my tag class directly without passing parameter in the jsp via attribute of tag ?
can I do like this?if yes,how can I?
thanks advance!
Hi,
Review pageContext, TagSupport from the JSP and Tag Extensions API. You can put the variable into any of the four scopes and retrieve it using the pageContext object.
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If you could give me some help I would appreciate it, as I have been worrying this issue for some time now and cannot figure out why this program will not compile. It tells me that there are a number of errors, and it appears that these errors are due to the fact that it will not allow me to reach from the private class to the primary for variables. Now, I have seen another program that is very similar and it does not have these issues. IF someone would explain to me what is going on here I think that I could fix it. Thanks
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.*;
import java.util.*;
import java.lang.*;
public class MortgageGUIv4_1 extends JFrame
public static void main(String[] args)
new MortgageGUIv4_1();
double MP, calcAPR, APR, adjustAPR, annualAPR;
double monthTerm, userTerm;
double userPrin;
boolean user = false;
String headers = "Payment No. \t\tRemainging Balance \tInterest Paid";
String []loanRates = {"7 years at 5.35%,15 years at 5.5, 30 years at 5.75%"};
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ButtonListener b1 = new ButtonListener();
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JPanel fourthRow = new JPanel();
JPanel fifthRow = new JPanel();
JPanel sixthRow = new JPanel();
JPanel seventhRow = new JPanel();
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JPanel buttonPanel = new JPanel();
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JLabel termRateLbl = new JLabel("Select a Term and Rate from the options listed");
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try
UIManager.setLookAndFeel("com.sun.java.swing.plaf.motif.MotifLookAndFeel");
catch(Exception e)
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JOptionPane.INFORMATION_MESSAGE);
MortgageGUIv4_1 winPane = new MortgageGUIv4_1();
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winPane.setSize(300,300);
winPane.setTitle("Dan's Mortgage GUI System");
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winPane.setLocation(200,100);
winPane.setVisible(true);
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fourthRow.setLayout(rowSetup);
fifthRow.setLayout(rowSetup);
sixthRow.setLayout(rowSetup);
seventhRow.setLayout(rowSetup);
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buttonPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
firstRow.add(userPrinLabel);
firstRow.add(userPrinvalue);
fourthRow.add(mortgagePayment);
fourthRow.add(totPayment);
fifthRow.add(termRateBx);
fifthRow.add(termRateLbl);
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fieldPanel.add(firstRow);
fieldPanel.add(fourthRow);
fieldPanel.add(fifthRow);
fieldPanel.add(sixthRow);
fieldPanel.add(seventhRow);
buttonPanel.add(buttonSubmit);
buttonPanel.add(buttonClear);
cont.add(fieldPanel, BorderLayout.CENTER);
cont.add(buttonPanel, BorderLayout.SOUTH);
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public void actionPerformed(ActionEvent e)
Object source = e.getSource();
//used the term user because this is the user input. When the user inputs a correct value then the program moves on
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//captures the user data entered in the text field and converts it to double
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if(userPrin <0)
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JOptionPane.INFORMATION_MESSAGE);
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}DanThank you one and all, in part to what you said here I when through and obviously had to make some serious changes to the code. Now it will compile however, when I try to run it I am getting the following error. do not use MortgageGUIv4_1.add() use MortgageGUIv4.1.getContentPane.add instead. I am at a loss for this one, as when I looked it up the only difference was that the one is awt and the other is swing. Could someone please let me know what I am missing.
Thanks
Dan
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
import java.text.*;
import java.util.*;
import java.lang.*;
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new MortgageGUIv4_1();
double MP, calcAPR, APR, adjustAPR, annualAPR;
double monthTerm, userTerm;
double userPrin;
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"Tarun Mangal" <[email protected]> wrote in message
news:400759e9$[email protected]..
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How can I assign javascript variables to jsp or java variables.?
How can I assign javascript variables to jsp or java variables.?
See I have generated some variables in the javascript which is on the jsp page. I want to assgin these variables to the jsp vaiables. Or how can I access javascript variables from jsp on the same jsp page.
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Hi ,
I have session variable defined using portals (forms or plsql portlets).
Can i access these variables using jsp portlets ??
This is an urgent requirement ..
Regards,
Vijaya"145822",
If your application with application id 100, for example, uses a common authentication scheme with application 200 (using the same cookie name in the case of an HTML DB style authentication scheme), then the two applications can run in the same session. A potential benefit of this, even if the two apps are not intricately related, is that the user has only to authenticate once per new session and will have access to both apps. If you set it up this way, then app 100 can access app 200's items in the same session using this function from within app 100: htmldb.application.fetch_app_item(p_item=>'ITEM_NAME',p_app=>200);Scott -
Custom component/tag class: ---which setters/getters do what?
Hi
I'm trying to create a custom component, but, there is a major concept that I do not understand...
---What are the setters/getters in the "component" class used for?...
---What are the setters/getters in the "tag" class used for?
Another way of asking is...
---Which setters/getters are used simply to keep track of attribute name/id/key?
---Which setters and getters refer to the actual objects that the attribute names point to?
The reason for my confusion is that nearly all "custom component" examples I've seen thus far, utilize attributes that point to "String" objects... (i.e., as opposed to ArrayList, HashMap, etc)...
This makes it difficult for me to distinguish whether the String values in the getters/setters are referring to the String name/"id" of the attribute...or, the String "value" of the attribute...
I have not been able to verify how I should code the getter/setters (and type casts) for other kinds of objects like ArrayLists, HashMaps, etc
For example, a typical logic mechanism Ive seen in the custom "tag" examples is as follows...
in a "tag" class...
if( tabledata != null )
if (isValueReference (tabledata))
FacesContext context = FacesContext.getCurrentInstance ();
Application app = context.getApplication ();
ValueBinding vb = app.createValueBinding (tabledata);
component.setValueBinding ("tabledata", vb);
else
component.getAttributes ().put ("tabledata", tabledata);
in the "component" class...
public void setTabledata (List tabledata)
this.tabledata = tabledata;
public List getTabledata ()
if(null != tabledata)
return tabledata;
ValueBinding _vb = getValueBinding ("tabledata");
if(_vb != null)
return (List)_vb.getValue (getFacesContext ());
else
return null;
}...considering the above code,
---when/where should the "tabledata" variable be referring the "name/id" of the attribute?...
---when/where should the "tabledata" variable be referring to the "value" of the attribute?...
...as, I need to change the type casting to adjust to what it should be...
***NOTE: This is one error that I'm getting, and I believe it is because I do not understand how getter/setter is used in "component" and "tag" classe, i.e., :
"org.apache.jasper.JasperException: jsp.error.beans.property.conversion
org.apache.jasper.runtime.JspRuntimeLibrary.getValueFromPropertyEditorManager(JspRuntimeLibrary.java:885)"...
Thanks for any help on this!
sdThe "tabledata" variable always refers the local value of the attribute.
When using a value binding to some backing bean,
the local value is null and the model value is owned by the bean.
You don't need any casting in the tag class nor the component class.
The setters/getters in the component class specify the type of the attributes.
Conversion from/to String to/from the type is done automatically if possible.
When the automatic conversion is impossible, you should specify f:converter
for the attribute.
Maybe you are looking for
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