envparametersconfiguration.java

一个完整的XACML工程,学习XACML技术的好例子!

     *           'pe.cfg' file.
     */
    public boolean isInPolicy(Element childToCheck)
    {
        NodeList nlist1 = ((Element)getParentNode()).getElementsByTagName("EnvironmentVariable");
        for (int i = 0; i < nlist.getLength() ; i++)
        {
            Element child = (Element)nlist1.item(i);
            if ((childToCheck.getAttribute("Name").equals(child.getAttribute("Name"))))
            {
                return true;
            }
        }        
        return false;
    }
    
    /**
     * Reads the Fields from the TextBoxes. Checks that the required entries 
     * to create a valid connection are not empty fields. Then adds the 
     * new Directory to the XML document.
     */
    public void addItem()
    {
        if (nameTextField.getText().intern().equals(""))
        {
            JOptionPane.showMessageDialog(xmlED, envParamsConfigError1, errorHeader, JOptionPane.ERROR_MESSAGE);
            return;
        } 
        
        if (dataTypeField.getSelectedIndex() <= 0)
        {
            JOptionPane.showMessageDialog(xmlED, envParamsConfigError1, errorHeader, JOptionPane.ERROR_MESSAGE);
            return;
        }
       
        Element child = xmlED.DOM.createElement("EnvironmentVariable"); 
        child.setAttribute("Name", nameTextField.getText());
        if (isInPolicy(child))
        {
            JOptionPane.showMessageDialog(xmlED, envParamsConfigError2, errorHeader, JOptionPane.ERROR_MESSAGE);
            return;
        }
        child.setAttribute("Type", (String)dataTypeField.getSelectedItem());
        xmlED.addItem(child, (Element)getParentNode());        
        nameTextField.grabFocus();
    }
    
    /**
     * Deletes the Currently Selected node from the NodeList.
     */    
    public void deleteItem()
    {
        if (this.getSelectedNode() != null)
        {  
            xmlED.deleteItem((Element)this.getSelectedNode(), ((Element)getParentNode()));
            //Set the TextFields to an empty value
            clearTextFields();
        }
    }
 
    /**
     * Method that resets all the Textfields to empty or a predefined value.
     */
    public void clearTextFields()
    {
        nameTextField.setText("");
        dataTypeField.setSelectedIndex(0);
    }
    
    /**
     * Method that replaces a Selected Node with the contents of the textfields,
     * Provided that the required fields have a valid Variable Definition, are not
     * empty.
     */
    public void replaceItem()
    {
        if (this.getSelectedNode() != null)
        {
            if (!nameTextField.getText().intern().equals("") && dataTypeField.getSelectedIndex() > 0)
            {
                //Setting the New Attributes to Replace --
                String attribs[] = { "Name", "Type" };
                String values[] = { nameTextField.getText(), (String)dataTypeField.getSelectedItem() }; 

                Element child = xmlED.DOM.createElement("EnvironmentVariable");
                child.setAttribute("Name", nameTextField.getText());
                if (isInPolicy(child) && !((Element)this.getSelectedNode()).getAttribute("Name").equals(nameTextField.getText()))
                {
                    JOptionPane.showMessageDialog(xmlED, envParamsConfigError2, errorHeader, JOptionPane.ERROR_MESSAGE);
                    return;
                }                                    
                                    
                xmlED.setAttributeValue((Element)this.getSelectedNode(), attribs, values);
                //----------------------------------------
            }
            else
            {
                JOptionPane.showMessageDialog(xmlED, envParamsConfigError1, errorHeader, JOptionPane.ERROR_MESSAGE);
                return;
            } 
        }        
    }
    
    /**
     * Method That Populates the NodeList with the current Environment Variables.
     */
    public void refreshView()
    {
        if (xmlED == null || xmlED.DOM == null) return;
        
        if (getParentNode() != null)
        {            
            NodeList nlist = ((Element)getParentNode()).getElementsByTagName("EnvironmentVariable");
            Node n;
            String envNames[] = new String[nlist.getLength()];
            
            for (int i = 0 ; i < nlist.getLength(); i++)
            {
                n = nlist.item(i);   
                envNames[i] = (((Element)n).getAttribute("Name"));
            }
            setNodeList(nlist, envNames);        
        }
    }
    
    /**
     * When the NodeItemList has a selected Element, the contents of that node, 
     * will populate the textfields, so the user will see exactly what the 
     * Environment Variable has as a defined type. 
     * <p> 
     * Users might then want to modify the Selected node, and therefore the 
     * refreshed textfields, would just need to be modified.
     * <p>
     * If nothing is selected in the NodeItemList, the textfields are reset
     * using the clearTextFields() method.
     */
    public void itemSelected()
    {      
        Element selectedNode; 

        super.itemSelected();
  
        addButton.setEnabled(false);
        replaceButton.setEnabled(false);
        
        if (getSelectedNode() == null)
        {
            clearTextFields();
        }
        else
        {
            selectedNode = (Element)getSelectedNode();
            nameTextField.setText(selectedNode.getAttribute("Name")); 
            dataTypeField.setSelectedItem(selectedNode.getAttribute("Type"));
        }
    }
    
    /**
     * The root node of the Current Document.
     *
     * @return   a node with the root Element of the 'pe.cfg' XML file.
     */
    public Node getParentNode()
    {
        return xmlED.DOM.getElementsByTagName("EnvironmentParameters").item(0);
    }     
    
    public void keyTyped(KeyEvent e)
    {   
    }
    
    /**
     * Method That enables/disables the appropriate buttons when the Text Fields
     * are being typed into.
     */
    public void keyPressed(KeyEvent e)
    {
    }
    
    public void keyReleased(KeyEvent e)
    {       
        if (e.getSource() == nameTextField)
        {
            if (this.listBox.getSelectedValue() == null &&
                    !nameTextField.getText().intern().equals("") &&
                    dataTypeField.getSelectedIndex() > 0)
            {
                addButton.setEnabled(true);
            }
            else if (!nameTextField.getText().intern().equals("") &&
                    dataTypeField.getSelectedIndex() > 0)
            {
                replaceButton.setEnabled(true);
                addButton.setEnabled(true);                
            }
            else if (nameTextField.getText().intern().equals("") ||
                    dataTypeField.getSelectedIndex() <= 0)
            {
                replaceButton.setEnabled(false);
                addButton.setEnabled(false);                
            }
        }
    }         
    
    public void actionPerformed(ActionEvent e)
    {
        if (e.getActionCommand().intern().equals("name_tf") && !nameTextField.getText().intern().equals(""))
        {
            dataTypeField.grabFocus();
        }
        else super.actionPerformed(e);
    }
    
    public void itemStateChanged(ItemEvent e)
    {
        if (dataTypeField.getSelectedIndex() <= 0)
        {
            replaceButton.setEnabled(false);
            addButton.setEnabled(false);
            return;
        }
        if (getSelectedIndex() >= 0 && e.getStateChange() == ItemEvent.SELECTED)
        {
            replaceButton.setEnabled(true);
        }
        else if (listBox.getSelectedValue() == null && 
            !nameTextField.getText().intern().equals("") && 
            !((String)dataTypeField.getSelectedItem()).equals("") &&
            getSelectedIndex() < 0)
                addButton.setEnabled(true);
        else if (!nameTextField.getText().intern().equals("") && 
                 !((String)dataTypeField.getSelectedItem()).equals("") &&
                 getSelectedIndex() < 0)
        {
            replaceButton.setEnabled(true);
            addButton.setEnabled(true);
        }
    }
}