HTMLMetaTags.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.nutch.parse;

import java.net.URL;
import java.util.Iterator;
import java.util.Properties;

/**
 * This class holds the information about HTML "meta" tags extracted from 
 * a page. Some special tags have convenience methods for easy checking.
 */
public class HTMLMetaTags {
  private boolean noIndex = false;

  private boolean noFollow = false;

  private boolean noCache = false;

  private URL baseHref = null;

  private boolean refresh = false;

  private int refreshTime = 0;

  private URL refreshHref = null;

  private Properties generalTags = new Properties();

  private Properties httpEquivTags = new Properties();

  /**
   * Sets all boolean values to <code>false</code>. Clears all other tags.
   */
  public void reset() {
    noIndex = false;
    noFollow = false;
    noCache = false;
    refresh = false;
    refreshTime = 0;
    baseHref = null;
    refreshHref = null;
    generalTags.clear();
    httpEquivTags.clear();
  }

  /**
   * Sets <code>noFollow</code> to <code>true</code>.
   */
  public void setNoFollow() {
    noFollow = true;
  }

  /**
   * Sets <code>noIndex</code> to <code>true</code>.
   */
  public void setNoIndex() {
    noIndex = true;
  }

  /**
   * Sets <code>noCache</code> to <code>true</code>.
   */
  public void setNoCache() {
    noCache = true;
  }

  /**
   * Sets <code>refresh</code> to the supplied value.
   */
  public void setRefresh(boolean refresh) {
    this.refresh = refresh;
  }

  /**
   * Sets the <code>baseHref</code>.
   */
  public void setBaseHref(URL baseHref) {
    this.baseHref = baseHref;
  }

  /**
   * Sets the <code>refreshHref</code>.
   */
  public void setRefreshHref(URL refreshHref) {
    this.refreshHref = refreshHref;
  }

  /**
   * Sets the <code>refreshTime</code>.
   */
  public void setRefreshTime(int refreshTime) {
    this.refreshTime = refreshTime;
  }

  /**
   * A convenience method. Returns the current value of <code>noIndex</code>.
   */
  public boolean getNoIndex() {
    return noIndex;
  }

  /**
   * A convenience method. Returns the current value of <code>noFollow</code>.
   */
  public boolean getNoFollow() {
    return noFollow;
  }

  /**
   * A convenience method. Returns the current value of <code>noCache</code>.
   */
  public boolean getNoCache() {
    return noCache;
  }

  /**
   * A convenience method. Returns the current value of <code>refresh</code>.
   */
  public boolean getRefresh() {
    return refresh;
  }

  /**
   * A convenience method. Returns the <code>baseHref</code>, if set, or
   * <code>null</code> otherwise.
   */
  public URL getBaseHref() {
    return baseHref;
  }

  /**
   * A convenience method. Returns the <code>refreshHref</code>, if set, or
   * <code>null</code> otherwise. The value may be invalid if
   * {@link #getRefresh()}returns <code>false</code>.
   */
  public URL getRefreshHref() {
    return refreshHref;
  }

  /**
   * A convenience method. Returns the current value of <code>refreshTime</code>.
   * The value may be invalid if {@link #getRefresh()}returns
   * <code>false</code>.
   */
  public int getRefreshTime() {
    return refreshTime;
  }

  /**
   * Returns all collected values of the general meta tags. Property names are
   * tag names, property values are "content" values.
   */
  public Properties getGeneralTags() {
    return generalTags;
  }

  /**
   * Returns all collected values of the "http-equiv" meta tags. Property names
   * are tag names, property values are "content" values.
   */
  public Properties getHttpEquivTags() {
    return httpEquivTags;
  }
  
  public String toString() {
    StringBuffer sb = new StringBuffer();
    sb.append("base=" + baseHref
            + ", noCache=" + noCache
            + ", noFollow=" + noFollow
            + ", noIndex=" + noIndex
            + ", refresh=" + refresh
            + ", refreshHref=" + refreshHref + "\n"
            );
    sb.append(" * general tags:\n");
    Iterator it = generalTags.keySet().iterator();
    while (it.hasNext()) {
      String key = (String)it.next();
      sb.append("   - " + key + "\t=\t" + generalTags.get(key) + "\n");
    }
    sb.append(" * http-equiv tags:\n");
    it = httpEquivTags.keySet().iterator();
    while (it.hasNext()) {
      String key = (String)it.next();
      sb.append("   - " + key + "\t=\t" + httpEquivTags.get(key) + "\n");
    }
    return sb.toString();
  }
}