Package org.pentaho.reporting.engine.classic.core.style

Source Code of org.pentaho.reporting.engine.classic.core.style.StyleKey

/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* Copyright (c) 2001 - 2009 Object Refinery Ltd, Pentaho Corporation and Contributors..  All rights reserved.
*/

package org.pentaho.reporting.engine.classic.core.style;

import java.io.ObjectStreamException;
import java.io.Serializable;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Iterator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.reporting.engine.classic.core.ClassicEngineBoot;
import org.pentaho.reporting.libraries.base.config.Configuration;
import org.pentaho.reporting.libraries.base.util.ObjectUtilities;

/**
* A style key represents a (key, class) pair.  Style keys are used to access style attributes defined in a
* <code>BandStyleSheet</code> or an <code>ElementStyleSheet</code>
* <p/>
* Note that this class also defines a static Hashtable in which all defined keys are stored.
*
* @author Thomas Morgner
* @see BandStyleKeys
* @see ElementStyleSheet
*/
public final class StyleKey implements Serializable, Cloneable
{
  private static final Log logger = LogFactory.getLog(StyleKey.class);

  /**
   * Shared storage for the defined keys.
   */
  private static HashMap definedKeys;
  private static int definedKeySize;
  private static StyleKey[] definedKeysArray;
  private static boolean locked;
 
  /**
   * The name of the style key.
   */
  public final String name;

  /**
   * The class of the value.
   */
  private Class valueType;

  /**
   * A unique int-key for the stylekey.
   */
  public final int identifier;

  /**
   * Whether this stylekey is transient. Transient keys will not be written when serializing a report.
   */
  private boolean trans;

  /**
   * Whether this stylekey is inheritable.
   */
  private boolean inheritable;

  /**
   * Creates a new style key.
   *
   * @param name        the name (never null).
   * @param valueType   the class of the value for this key (never null).
   * @param inheritable a flag indicating whether the value will be inherited from parent bands to child elements.
   * @param trans       a flag indicating whether the style property should be saved. Transient properties are temporary
   *                    artifacts and should not be stored in report definitions.
   */
  private StyleKey(final String name,
                   final Class valueType,
                   final boolean trans,
                   final boolean inheritable)
  {
    if (name == null)
    {
      throw new NullPointerException("StyleKey.setName(...): null not permitted.");
    }
    if (valueType == null)
    {
      throw new NullPointerException("ValueType must not be null");
    }
    this.valueType = valueType;
    this.name = name;
    this.identifier = StyleKey.definedKeys.size();
    this.trans = trans;
    this.inheritable = inheritable;
  }

  /**
   * Returns the name of the key.
   *
   * @return the name.
   */
  public String getName()
  {
    return name;
  }

  /**
   * Returns the class of the value for this key.
   *
   * @return the class.
   */
  public Class getValueType()
  {
    return valueType;
  }

  /**
   * Returns the key with the specified name. The given type is not checked against a possibly alredy defined
   * definition, it is assumed that the type is only given for a new key definition.
   *
   * @param name      the name.
   * @param valueType the class.
   * @return the style key.
   */
  public static StyleKey getStyleKey(final String name, final Class valueType)
  {
    return getStyleKey(name, valueType, false, true);
  }

  /**
   * Returns the key with the specified name. The given type is not checked against a possibly alredy defined
   * definition, it is assumed that the type is only given for a new key definition.
   *
   * @param name        the name.
   * @param valueType   the class.
   * @param inheritable a flag indicating whether the value will be inherited from parent bands to child elements.
   * @param trans       a flag indicating whether the style property should be saved. Transient properties are temporary
   *                    artifacts and should not be stored in report definitions.
   * @return the style key.
   */
  public static synchronized StyleKey getStyleKey(final String name,
                                                  final Class valueType,
                                                  final boolean trans,
                                                  final boolean inheritable)
  {
    if (locked)
    {
      throw new IllegalStateException("StyleKeys have been locked after booting was completed.");
    }
    if (definedKeys == null)
    {
      definedKeys = new HashMap();
      definedKeySize = 0;
    }
    StyleKey key = (StyleKey) definedKeys.get(name);
    if (key == null)
    {
      key = new StyleKey(name, valueType, trans, inheritable);
      definedKeys.put(name, key);
      definedKeySize = definedKeys.size();
      definedKeysArray = null;
    }
    return key;
  }

  public static synchronized void lock()
  {
    locked = true;
  }

  /**
   * Returns the key with the specified name.
   *
   * @param name the name.
   * @return the style key.
   */
  public static synchronized StyleKey getStyleKey(final String name)
  {
    if (definedKeys == null)
    {
      return null;
    }
    else
    {
      return (StyleKey) definedKeys.get(name);
    }
  }

  /**
   * Indicates whether some other object is "equal to" this one.
   *
   * @param o the reference object with which to compare.
   * @return <code>true</code> if this object is the same as the obj argument; <code>false</code> otherwise.
   */
  public boolean equals(final Object o)
  {
    if (this == o)
    {
      return true;
    }
    if (!(o instanceof StyleKey))
    {
      return false;
    }

    final StyleKey key = (StyleKey) o;

    if (!name.equals(key.name))
    {
      return false;
    }
    if (!valueType.equals(key.valueType))
    {
      return false;
    }

    return true;
  }

  /**
   * Returns a hash code value for the object. This method is supported for the benefit of hashtables such as those
   * provided by <code>java.util.Hashtable</code>.
   * <p/>
   *
   * @return a hash code value for this object.
   */
  public int hashCode()
  {
    return identifier;
  }

  /**
   * Replaces the automaticly generated instance with one of the defined stylekey instances or creates a new stylekey.
   *
   * @return the resolved element
   * @throws ObjectStreamException if the element could not be resolved.
   */
  private Object readResolve()
      throws ObjectStreamException
  {
    synchronized (StyleKey.class)
    {
      final StyleKey key = StyleKey.getStyleKey(name);
      if (key != null)
      {
        return key;
      }
      return StyleKey.getStyleKey(name, valueType, trans, inheritable);
    }
  }

  public boolean isTransient()
  {
    return trans;
  }

  /**
   * Returns a string representation of the object.
   *
   * @return a string representation of the object.
   */
  public String toString()
  {
    final StringBuffer b = new StringBuffer(100);
    b.append("StyleKey={name='");
    b.append(getName());
    b.append("', valueType='");
    b.append(getValueType());
    b.append("'}");
    return b.toString();
  }

  public Object clone()
      throws CloneNotSupportedException
  {
    return super.clone();
  }

  public boolean isInheritable()
  {
    return inheritable;
  }

  public int getIdentifier()
  {
    return identifier;
  }

  public static int getDefinedStyleKeyCount()
  {
    return definedKeySize;
  }

  public static synchronized StyleKey[] getDefinedStyleKeys()
  {
    if (definedKeys == null)
    {
      throw new IllegalStateException("The engine has not been booted and the default keys have no been registered yet.");
    }
    if (definedKeysArray != null)
    {
      assertNoNullEntries();
      return definedKeysArray.clone();
    }

    final StyleKey[] keys = (StyleKey[]) definedKeys.values().toArray(new StyleKey[definedKeys.size()]);
    definedKeysArray = keys.clone();
    for (int i = 0; i < keys.length; i++)
    {
      final StyleKey key = keys[i];
      definedKeysArray[key.identifier] = key;
    }
    assertNoNullEntries();
    return definedKeysArray.clone();
  }

  public static void assertNoNullEntries()
  {
    for (int i = 0; i < definedKeysArray.length; i++)
    {
      final StyleKey styleKey = definedKeysArray[i];
      if (styleKey == null)
      {
        throw new NullPointerException();
      }
    }
  }


  /**
   * @noinspection ProhibitedExceptionCaught
   */
  public static synchronized void registerDefaults()
  {
    final Configuration config = ClassicEngineBoot.getInstance().getGlobalConfig();
    final Iterator it = config.findPropertyKeys("org.pentaho.reporting.engine.classic.core.stylekeys.");
    final ClassLoader classLoader = ObjectUtilities.getClassLoader(StyleKey.class);

    while (it.hasNext())
    {
      final String key = (String) it.next();
      final String keyClass = config.getConfigProperty(key);
      try
      {
        final Class c = Class.forName(keyClass, false, classLoader);
        registerClass(c);
      }
      catch (ClassNotFoundException e)
      {
        // ignore that class
        logger.warn("Unable to register keys from " + keyClass);
      }
      catch (NullPointerException e)
      {
        // ignore invalid values as well.
        logger.warn("Unable to register keys from " + keyClass);
      }
    }

  }

  public static synchronized void registerClass(final Class c)
  {
    // Log.debug ("Registering stylekeys from " + c);
    try
    {
      final Field[] fields = c.getFields();
      for (int i = 0; i < fields.length; i++)
      {
        final Field field = fields[i];
        final int modifiers = field.getModifiers();
        if (Modifier.isPublic(modifiers) &&
            Modifier.isStatic(modifiers))
        {
          if (Modifier.isFinal(modifiers) == false)
          {
            logger.warn("Invalid implementation: StyleKeys should be 'public static final': " + c);
          }
          if (field.getType().isAssignableFrom(StyleKey.class))
          {
            //noinspection UnusedDeclaration
            final StyleKey value = (StyleKey) field.get(null);
            // ignore the returned value, all we want is to trigger the key
            // creation
            // Log.debug ("Loaded key " + value);
          }
        }
      }
    }
    catch (IllegalAccessException e)
    {
      // wont happen, we've checked it..
      logger.warn("Unable to register keys from " + c.getName());
    }
  }

}
TOP

Related Classes of org.pentaho.reporting.engine.classic.core.style.StyleKey

TOP
Copyright © 2018 www.massapi.com. All rights reserved.
All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.