/*
* Copyright 2001,2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.webapp.admin;
import java.io.IOException;
import java.net.URLEncoder;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagSupport;
/**
* <p>JSP custom tag that renders a tree control represented by the
* <code>TreeControl</code> and <code>TreeControlNode</code> classes.
* This tag has the following user-settable attributes:</p>
* <ul>
* <li><strong>action</strong> - Hyperlink to which expand/contract actions
* should be sent, with a string "<code>{name}</code> marking where
* the node name of the affected node should be included.</li>
* <li><strong>images</strong> - Name of the directory containing the images
* for our icons, relative to the page including this tag. If not
* specified, defaults to "images".</li>
* <li><strong>scope</strong> - Attribute scope in which the <code>tree</code>
* attribute is to be found (page, request, session, application). If
* not specified, the attribute is searched for in all scopes.</li>
* <li><strong>style</strong> - CSS style <code>class</code> to be applied
* to be applied to the entire rendered output of the tree control.
* If not specified, no style class is applied.</li>
* <li><strong>styleSelected</strong> - CSS style <code>class</code> to be
* applied to the text of any element that is currently selected. If not
* specified, no additional style class is applied.</li>
* <li><strong>styleUnselected</strong> - CSS style <code>class</code> to be
* applied to the text of any element that is not currently selected.
* If not specified, no additional style class is applied.</li>
* <li><strong>tree</strong> - Attribute name under which the
* <code>TreeControl</code> bean of the tree we are rendering
* is stored, in the scope specified by the <code>scope</code>
* attribute. This attribute is required.</li>
* </ul>
*
* <strong>FIXME</strong> - Internationalize the exception messages!
*
* @author Craig R. McClanahan
* @version $Revision: 303561 $ $Date: 2004-12-01 22:49:01 -0500 (Wed, 01 Dec 2004) $
*/
public class TreeControlTag extends TagSupport {
/**
* The default directory name for icon images.
*/
static final String DEFAULT_IMAGES = "images";
/**
* The names of tree state images that we need.
*/
static final String IMAGE_HANDLE_DOWN_LAST = "handledownlast.gif";
static final String IMAGE_HANDLE_DOWN_MIDDLE = "handledownmiddle.gif";
static final String IMAGE_HANDLE_RIGHT_LAST = "handlerightlast.gif";
static final String IMAGE_HANDLE_RIGHT_MIDDLE = "handlerightmiddle.gif";
static final String IMAGE_LINE_LAST = "linelastnode.gif";
static final String IMAGE_LINE_MIDDLE = "linemiddlenode.gif";
static final String IMAGE_LINE_VERTICAL = "linevertical.gif";
// ------------------------------------------------------------- Properties
/**
* The hyperlink to be used for submitting requests to expand and
* contract tree nodes. The placeholder "<code>{name}</code>" will
* be replaced by the <code>name</code> property of the current
* tree node.
*/
protected String action = null;
public String getAction() {
return (this.action);
}
public void setAction(String action) {
this.action = action;
}
/**
* The name of the directory containing the images for our icons,
* relative to the page including this tag.
*/
protected String images = DEFAULT_IMAGES;
public String getImages() {
return (this.images);
}
public void setImages(String images) {
this.images = images;
}
/**
* The name of the scope in which to search for the <code>tree</code>
* attribute. Must be "page", "request", "session", or "application"
* (or <code>null</code> for an ascending-visibility search).
*/
protected String scope = null;
public String getScope() {
return (this.scope);
}
public void setScope(String scope) {
if (!"page".equals(scope) &&
!"request".equals(scope) &&
!"session".equals(scope) &&
!"application".equals(scope))
throw new IllegalArgumentException("Invalid scope '" +
scope + "'");
this.scope = scope;
}
/**
* The CSS style <code>class</code> to be applied to the entire tree.
*/
protected String style = null;
public String getStyle() {
return (this.style);
}
public void setStyle(String style) {
this.style = style;
}
/**
* The CSS style <code>class</code> to be applied to the text
* of selected nodes.
*/
protected String styleSelected = null;
public String getStyleSelected() {
return (this.styleSelected);
}
public void setStyleSelected(String styleSelected) {
this.styleSelected = styleSelected;
}
/**
* The CSS style <code>class</code> to be applied to the text
* of unselected nodes.
*/
protected String styleUnselected = null;
public String getStyleUnselected() {
return (this.styleUnselected);
}
public void setStyleUnselected(String styleUnselected) {
this.styleUnselected = styleUnselected;
}
/**
* The name of the attribute (in the specified scope) under which our
* <code>TreeControl</code> instance is stored.
*/
protected String tree = null;
public String getTree() {
return (this.tree);
}
public void setTree(String tree) {
this.tree = tree;
}
// --------------------------------------------------------- Public Methods
/**
* Render this tree control.
*
* @exception JspException if a processing error occurs
*/
public int doEndTag() throws JspException {
TreeControl treeControl = getTreeControl();
JspWriter out = pageContext.getOut();
try {
out.print
("<table border=\"0\" cellspacing=\"0\" cellpadding=\"0\"");
if (style != null) {
out.print(" class=\"");
out.print(style);
out.print("\"");
}
out.println(">");
int level = 0;
TreeControlNode node = treeControl.getRoot();
render(out, node, level, treeControl.getWidth(), true);
out.println("</table>");
} catch (IOException e) {
throw new JspException(e);
}
return (EVAL_PAGE);
}
/**
* Release all state information set by this tag.
*/
public void release() {
this.action = null;
this.images = DEFAULT_IMAGES;
this.scope = null;
this.style = null;
this.styleSelected = null;
this.styleUnselected = null;
this.tree = null;
}
// ------------------------------------------------------ Protected Methods
/**
* Return the <code>TreeControl</code> instance for the tree control that
* we are rendering.
*
* @exception JspException if no TreeControl instance can be found
*/
protected TreeControl getTreeControl() throws JspException {
Object treeControl = null;
if (scope == null)
treeControl = pageContext.findAttribute(tree);
else if ("page".equals(scope))
treeControl =
pageContext.getAttribute(tree, PageContext.PAGE_SCOPE);
else if ("request".equals(scope))
treeControl =
pageContext.getAttribute(tree, PageContext.REQUEST_SCOPE);
else if ("session".equals(scope))
treeControl =
pageContext.getAttribute(tree, PageContext.SESSION_SCOPE);
else if ("application".equals(scope))
treeControl =
pageContext.getAttribute(tree, PageContext.APPLICATION_SCOPE);
if (treeControl == null)
throw new JspException("Cannot find tree control attribute '" +
tree + "'");
else if (!(treeControl instanceof TreeControl))
throw new JspException("Invalid tree control attribute '" +
tree + "'");
else
return ((TreeControl) treeControl);
}
/**
* Render the specified node, as controlled by the specified parameters.
*
* @param out The <code>JspWriter</code> to which we are writing
* @param node The <code>TreeControlNode</code> we are currently
* rendering
* @param level The indentation level of this node in the tree
* @param width Total displayable width of the tree
* @param last Is this the last node in a list?
*
* @exception IOException if an input/output error occurs
*/
protected void render(JspWriter out, TreeControlNode node,
int level, int width, boolean last)
throws IOException {
HttpServletResponse response =
(HttpServletResponse) pageContext.getResponse();
// if the node is root node and the label value is
// null, then do not render root node in the tree.
if ("ROOT-NODE".equalsIgnoreCase(node.getName()) &&
(node.getLabel() == null)) {
// Render the children of this node
TreeControlNode children[] = node.findChildren();
int lastIndex = children.length - 1;
int newLevel = level + 1;
for (int i = 0; i < children.length; i++) {
render(out, children[i], newLevel, width, i == lastIndex);
}
return;
}
// Render the beginning of this node
out.println(" <tr valign=\"middle\">");
// Create the appropriate number of indents
for (int i = 0; i < level; i++) {
int levels = level - i;
TreeControlNode parent = node;
for (int j = 1; j <= levels; j++)
parent = parent.getParent();
if (parent.isLast())
out.print(" <td></td>");
else {
out.print(" <td><img src=\"");
out.print(images);
out.print("/");
out.print(IMAGE_LINE_VERTICAL);
out.print("\" alt=\"\" border=\"0\"></td>");
}
out.println();
}
// Render the tree state image for this node
// HACK to take into account special characters like = and &
// in the node name, could remove this code if encode URL
// and later request.getParameter() could deal with = and &
// character in parameter values.
String encodedNodeName = URLEncoder.encode(node.getName(),TomcatTreeBuilder.URL_ENCODING);
String action = replace(getAction(), "{name}", encodedNodeName);
String updateTreeAction =
replace(getAction(), "tree={name}", "select=" + encodedNodeName);
updateTreeAction =
((HttpServletResponse) pageContext.getResponse()).
encodeURL(updateTreeAction);
out.print(" <td>");
if ((action != null) && !node.isLeaf()) {
out.print("<a href=\"");
out.print(response.encodeURL(action));
out.print("\">");
}
out.print("<img src=\"");
out.print(images);
out.print("/");
if (node.isLeaf()) {
if (node.isLast())
out.print(IMAGE_LINE_LAST);
else
out.print(IMAGE_LINE_MIDDLE);
out.print("\" alt=\"");
} else if (node.isExpanded()) {
if (node.isLast())
out.print(IMAGE_HANDLE_DOWN_LAST);
else
out.print(IMAGE_HANDLE_DOWN_MIDDLE);
out.print("\" alt=\"close node");
} else {
if (node.isLast())
out.print(IMAGE_HANDLE_RIGHT_LAST);
else
out.print(IMAGE_HANDLE_RIGHT_MIDDLE);
out.print("\" alt=\"expand node");
}
out.print("\" border=\"0\">");
if ((action != null) && !node.isLeaf())
out.print("</a>");
out.println("</td>");
// Calculate the hyperlink for this node (if any)
String hyperlink = null;
if (node.getAction() != null)
hyperlink = ((HttpServletResponse) pageContext.getResponse()).
encodeURL(node.getAction());
// Render the icon for this node (if any)
out.print(" <td colspan=\"");
out.print(width - level + 1);
out.print("\">");
if (node.getIcon() != null) {
if (hyperlink != null) {
out.print("<a href=\"");
out.print(hyperlink);
out.print("\"");
String target = node.getTarget();
if(target != null) {
out.print(" target=\"");
out.print(target);
out.print("\"");
}
// to refresh the tree in the same 'self' frame
out.print(" onclick=\"");
out.print("self.location.href='" + updateTreeAction + "'");
out.print("\"");
out.print(">");
}
out.print("<img src=\"");
out.print(images);
out.print("/");
out.print(node.getIcon());
out.print("\" alt=\"");
out.print("\" border=\"0\">");
if (hyperlink != null)
out.print("</a>");
}
// Render the label for this node (if any)
if (node.getLabel() != null) {
String labelStyle = null;
if (node.isSelected() && (styleSelected != null))
labelStyle = styleSelected;
else if (!node.isSelected() && (styleUnselected != null))
labelStyle = styleUnselected;
if (hyperlink != null) {
// Note the leading space so that the text has some space
// between it and any preceding images
out.print(" <a href=\"");
out.print(hyperlink);
out.print("\"");
String target = node.getTarget();
if(target != null) {
out.print(" target=\"");
out.print(target);
out.print("\"");
}
if (labelStyle != null) {
out.print(" class=\"");
out.print(labelStyle);
out.print("\"");
}
// to refresh the tree in the same 'self' frame
out.print(" onclick=\"");
out.print("self.location.href='" + updateTreeAction + "'");
out.print("\"");
out.print(">");
} else if (labelStyle != null) {
out.print("<span class=\"");
out.print(labelStyle);
out.print("\">");
}
out.print(node.getLabel());
if (hyperlink != null)
out.print("</a>");
else if (labelStyle != null)
out.print("</span>");
}
out.println("</td>");
// Render the end of this node
out.println(" </tr>");
// Render the children of this node
if (node.isExpanded()) {
TreeControlNode children[] = node.findChildren();
int lastIndex = children.length - 1;
int newLevel = level + 1;
for (int i = 0; i < children.length; i++) {
render(out, children[i], newLevel, width, i == lastIndex);
}
}
}
/**
* Replace any occurrence of the specified placeholder in the specified
* template string with the specified replacement value.
*
* @param template Pattern string possibly containing the placeholder
* @param placeholder Placeholder expression to be replaced
* @param value Replacement value for the placeholder
*/
protected String replace(String template, String placeholder,
String value) {
if (template == null)
return (null);
if ((placeholder == null) || (value == null))
return (template);
while (true) {
int index = template.indexOf(placeholder);
if (index < 0)
break;
StringBuffer temp = new StringBuffer(template.substring(0, index));
temp.append(value);
temp.append(template.substring(index + placeholder.length()));
template = temp.toString();
}
return (template);
}
}