checkboxtag.java

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package com.laoer.bbscs.web.taglib;

import javax.servlet.jsp.*;

import org.apache.struts.taglib.*;
import org.apache.struts.taglib.html.*;
import org.apache.struts.util.*;

import java.lang.reflect.InvocationTargetException;
import java.util.Arrays;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;

import org.apache.commons.beanutils.PropertyUtils;
import org.apache.commons.collections.IteratorUtils;

/**
 * <p>Title: Tianyi BBS</p>
 *
 * <p>Description: BBSCS</p>
 *
 * <p>Copyright: Copyright (c) 2006</p>
 *
 * <p>Company: Laoer.com</p>
 *
 * @author Gong Tianyi
 * @version 7.0
 */
public class CheckboxTag
    extends BaseHandlerTag {

  // ----------------------------------------------------- Instance Variables

  /**
   * The message resources for this package.
   */
  protected static MessageResources messages =
      MessageResources.getMessageResources(Constants.Package + ".LocalStrings");

  /**
   * The name of the bean containing our underlying property.
   */
  protected String name = Constants.BEAN_KEY;

  public String getName() {
    return (this.name);
  }

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

  /**
   * The property name for this field.
   */
  protected String property = null;

  /**
   * The body content of this tag (if any).
   */
  protected String text = null;

  /**
   * The server value for this option.
   */
  protected String value = null;
  private String valueName = null;
  private String valueProperty = null;
  private String collection = null;
  //private Iterator collIterator;

  // ------------------------------------------------------------- Properties

  /**
   * Return the property name.
   */
  public String getProperty() {

    return (this.property);

  }

  /**
   * Set the property name.
   *
   * @param property The new property name
   */
  public void setProperty(String property) {

    this.property = property;

  }

  /**
   * Return the server value.
   */
  public String getValue() {

    return (this.value);

  }

  public String getValueName() {
    return valueName;
  }

  public String getValueProperty() {
    return valueProperty;
  }

  public String getCollection() {
    return collection;
  }

  /**
   * Set the server value.
   *
   * @param value The new server value
   */
  public void setValue(String value) {

    this.value = value;

  }

  public void setValueName(String valueName) {
    this.valueName = valueName;
  }

  public void setValueProperty(String valueProperty) {
    this.valueProperty = valueProperty;
  }

  public void setCollection(String collection) {
    this.collection = collection;
  }

  // --------------------------------------------------------- Public Methods

  /**
   * Generate the required input tag.
   * <p>
   * Support for indexed property since Struts 1.1
   *
   * @exception JspException if a JSP exception has occurred
   */
  public int doStartTag() throws JspException {
    //if (this.collection != null) {
    //  this.collIterator = getIterator(collection, null);
    //}
    // Create an appropriate "input" element based on our parameters
    StringBuffer results = new StringBuffer("<input type=\"checkbox\"");
    results.append(" name=\"");

    if (indexed) {
      prepareIndex(results, name);
    }

    results.append(this.property);
    results.append("\"");
    if (accesskey != null) {
      results.append(" accesskey=\"");
      results.append(accesskey);
      results.append("\"");
    }

    if (tabindex != null) {
      results.append(" tabindex=\"");
      results.append(tabindex);
      results.append("\"");
    }

    results.append(" value=\"");
    value = this.getIterateValue();

    if (value == null) {
      results.append("on");
    }
    else {
      results.append(value);
    }

    results.append("\"");

    if (this.isChecked()) {
      results.append(" checked=\"checked\"");
    }

    results.append(prepareEventHandlers());
    results.append(prepareStyles());
    results.append(getElementClose());

    // Print this field to our output writer
    TagUtils.getInstance().write(pageContext, results.toString());

    // Continue processing this page
    this.text = null;
    return (EVAL_BODY_TAG);
    //return this.EVAL_BODY_BUFFERED;
  }

  /**
   * Determines if the checkbox should be checked.
   * @return true if checked="checked" should be rendered.
   * @throws JspException
   * @since Struts 1.2
   */
  protected boolean isChecked() throws JspException {
    if (this.collection == null) {
      Object result =
          TagUtils.getInstance().lookup(pageContext, name, property, null);

      if (result == null) {
        result = "";
      }

      result = result.toString();

      String checked = (String) result;
      return (
          checked.equalsIgnoreCase(this.value)
          || checked.equalsIgnoreCase("true")
          || checked.equalsIgnoreCase("yes")
          || checked.equalsIgnoreCase("on"));
    }
    else {
      String nowValue = this.getIterateValue();
      //System.out.println("nowValue:" + nowValue);
      Iterator collIterator = getIterator(collection, null);
      //System.out.println(collIterator);
      while (collIterator.hasNext()) {
        //System.out.println("");
        Object bean = collIterator.next();
        //System.out.println("bean:" + bean);
        if (nowValue.equals(String.valueOf(bean))) {
          return true;
        }
      }
      collIterator = null;
      return false;
    }
  }

  protected String getIterateValue() throws JspException {
    if (this.valueName != null && this.valueProperty != null) {
      Object iValue = TagUtils.getInstance().lookup(pageContext, valueName, valueProperty, null);
      if (iValue == null) {
        return this.value;
      }
      return iValue.toString();
    }
    else {
      return this.value;
    }
  }

  /**
   * Return an iterator for the option labels or values, based on our
   * configured properties.
   *
   * @param name Name of the bean attribute (if any)
   * @param property Name of the bean property (if any)
   *
   * @exception JspException if an error occurs
   */
  protected Iterator getIterator(String name, String property) throws JspException {

    // Identify the bean containing our collection
    String beanName = name;
    if (beanName == null) {
      beanName = Constants.BEAN_KEY;
    }
    Object bean = new Object();
    bean = TagUtils.getInstance().lookup(pageContext, beanName, null);
    if (bean == null) {
      throw new JspException(messages.getMessage("getter.bean", beanName));
    }

    // Identify the collection itself
    Object collection = bean;
    if (property != null) {
      try {
        collection = PropertyUtils.getProperty(bean, property);
        if (collection == null) {
          throw new JspException(messages.getMessage("getter.property", property));
        }
      }
      catch (IllegalAccessException e) {
        throw new JspException(messages.getMessage("getter.access", property, name));
      }
      catch (InvocationTargetException e) {
        Throwable t = e.getTargetException();
        throw new JspException(
            messages.getMessage("getter.result", property, t.toString()));
      }
      catch (NoSuchMethodException e) {
        throw new JspException(messages.getMessage("getter.method", property, name));
      }
    }

    // Construct and return an appropriate iterator
    if (collection.getClass().isArray()) {
      collection = Arrays.asList( (Object[]) collection);
    }

    if (collection instanceof Collection) {
      return ( ( (Collection) collection).iterator());

    }
    else if (collection instanceof Iterator) {
      return ( (Iterator) collection);

    }
    else if (collection instanceof Map) {
      return ( ( (Map) collection).entrySet().iterator());

    }
    else if (collection instanceof Enumeration) {
      return IteratorUtils.asIterator( (Enumeration) collection);

    }
    else {
      throw new JspException(
          messages.getMessage("optionsTag.iterator", collection.toString()));
    }
  }

  protected Object[] getObjArray(String name, String property) throws JspException {

    // Identify the bean containing our collection
    String beanName = name;
    if (beanName == null) {
      beanName = Constants.BEAN_KEY;
    }
    Object bean = new Object();
    bean = TagUtils.getInstance().lookup(pageContext, beanName, null);
    if (bean == null) {
      throw new JspException(messages.getMessage("getter.bean", beanName));
    }

    // Identify the collection itself
    Object collection = bean;
    if (property != null) {
      try {
        collection = PropertyUtils.getProperty(bean, property);
        if (collection == null) {
          throw new JspException(messages.getMessage("getter.property", property));
        }
      }
      catch (IllegalAccessException e) {
        throw new JspException(messages.getMessage("getter.access", property, name));
      }
      catch (InvocationTargetException e) {
        Throwable t = e.getTargetException();
        throw new JspException(
            messages.getMessage("getter.result", property, t.toString()));
      }
      catch (NoSuchMethodException e) {
        throw new JspException(messages.getMessage("getter.method", property, name));
      }
    }

    // Construct and return an appropriate iterator
    //if (collection.getClass().isArray()) {
    //  collection = Arrays.asList( (Object[]) collection);
    //}

    return (Object[])collection;
  }

  /**
   * Save the associated label from the body content.
   *
   * @exception JspException if a JSP exception has occurred
   */
  public int doAfterBody() throws JspException {

    if (bodyContent != null) {
      String value = bodyContent.getString().trim();
      if (value.length() > 0) {
        text = value;
      }
    }
    return (SKIP_BODY);

  }

  /**
   * Process the remainder of this page normally.
   *
   * @exception JspException if a JSP exception has occurred
   */
  public int doEndTag() throws JspException {

    // Render any description for this checkbox
    if (text != null) {
      TagUtils.getInstance().write(pageContext, text);
    }

    // Evaluate the remainder of this page
    return (EVAL_PAGE);

  }

  /**
   * Release any acquired resources.
   */
  public void release() {

    super.release();
    name = Constants.BEAN_KEY;
    property = null;
    text = null;
    value = null;

  }

}