usemenudisplayertag.java

Struts Menu这是为基于JSP和Struts的应用程序提供的Web菜单框架。菜单可以在一个XML文件中定义

package net.sf.navigator.taglib.el;

import java.util.Locale;
import java.util.ResourceBundle;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.jstl.fmt.LocalizationContext;
import javax.servlet.jsp.tagext.Tag;

import net.sf.navigator.displayer.MenuDisplayer;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.Globals;
import org.apache.taglibs.standard.tag.common.fmt.BundleSupport;


/**
 * This tag acts the same as net.sf.navigator.taglib.UseMenuDisplayerTag, except
 * that it allows JSTL Expressions in all it's attributes.
 *
 * @author Matt Raible
 * @version $Revision: 1.3 $ $Date: 2004/03/23 16:50:37 $
 */
public class UseMenuDisplayerTag
    extends net.sf.navigator.taglib.UseMenuDisplayerTag {
    private static Log log = LogFactory.getLog(UseMenuDisplayerTag.class);
    private String name;
    private String bundle;
    private String config = MenuDisplayer.DEFAULT_CONFIG;
    private String locale;
    private String permissions;
    private String repository;

    public void setName(String name) {
        this.name = name;
    }

    public void setBundle(String bundle) {
        this.bundle = bundle;
    }

    public void setConfig(String config) {
        this.config = config;
    }

    public void setLocale(String locale) {
        this.locale = locale;
    }

    public void setPermissions(String permissions) {
        this.permissions = permissions;
    }

    public void setRepository(String key) {
        this.repository = key;
    }

    public UseMenuDisplayerTag() {
        super();
        init();
    }

    private void init() {
        name = null;
        bundle = null;
        config = null;
        locale = null;
        permissions = null;
        repository = null;
    }

    public void release() {
        super.release();
        init();
    }

    public int doStartTag() throws JspException {
        evaluateExpressions();

        // Default to JSTL Bundle to use (for EL Tag)
        Tag tag = findAncestorWithClass(this, BundleSupport.class);

        if (tag != null) {
            BundleSupport parent = (BundleSupport) tag;
            rb = parent.getLocalizationContext().getResourceBundle();
        } else {
            // check for the localizationContext in applicationScope, set in web.xml
            LocalizationContext localization =
                BundleSupport.getLocalizationContext(pageContext);

            if (localization != null) {
                rb = localization.getResourceBundle();
            }
        }

        return super.doStartTag();
    }

    private void evaluateExpressions() throws JspException {
        ExpressionEvaluator eval = new ExpressionEvaluator(this, pageContext);
        String s;

        if ((s = eval.evalString("name", name)) != null) {
            super.setName(s);
        }

        if ((s = eval.evalString("bundle", bundle)) != null) {
            super.setBundle(s);
        }

        if ((s = eval.evalString("config", config)) != null) {
            super.setConfig(s);
        }

        if ((s = eval.evalString("locale", locale)) != null) {
            super.setLocale(s);
        }

        if ((s = eval.evalString("permissions", permissions)) != null) {
            super.setPermissions(s);
        }

        if ((s = eval.evalString("repository", repository)) != null) {
            super.setRepository(s);
        }
    }
}