AOO410/main/wizards/com/sun/star/wizards/ui/event/DataAware.java - openoffice - Git at Google

 /**************************************************************
  *
  * 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 com.sun.star.wizards.ui.event;

 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
 import com.sun.star.wizards.common.PropertyNames;

 /**
  * @author rpiterman
  * DataAware objects are used to live-synchronize UI and DataModel/DataObject.
  * It is used as listener on UI events, to keep the DataObject up to date.
  * This class, as a base abstract class, sets a frame of functionality,
  * delegating the data Object get/set methods to a Value object,
  * and leaving the UI get/set methods abstract.
  * Note that event listenning is *not* a part of this model.
  * the updateData() or updateUI() methods should be porogramatically called.
  * in child classes, the updateData() will be binded to UI event calls.
  * <br><br>
  * This class holds references to a Data Object and a Value object.
  * The Value object "knows" how to get and set a value from the
  * Data Object.
  */
 public abstract class DataAware {

     /**
      * this is the data object.
      */
     protected Object dataObject;
     //protected Method setMethod;
     //protected Method getMethod;
     /**
      * A Value Object knows how to get/set a value
      * from/to the data object.
      */
     protected Value value;

     /**
      * creates a DataAware object for the given data object and Value object.
      * @param dataObject_
      * @param value_
      */
     protected DataAware(Object dataObject_, Value value_) {
         dataObject = dataObject_;
         value = value_;
         //getMethod = createGetMethod(dataPropName, dataObject);
         //setMethod = createSetMethod(dataPropName, dataObject, getMethod.getReturnType());
     }

     /**
      * returns the data object.
      * @return
      */
     public Object getDataObject() {
         return dataObject;
     }

     /**
      * sets a new data object. Optionally
      * update the UI.
      * @param obj the new data object.
      * @param updateUI if true updateUI() will be called.
      */
     public void setDataObject(Object obj, boolean updateUI) {

         if (obj != null && !value.isAssignable(obj.getClass()))
             throw new ClassCastException("can not cast new DataObject to original Class");

         dataObject = obj;

         if (updateUI)
             updateUI();

     }

     /**
      * Sets the given value to the data object.
      * this method delegates the job to the
      * Value object, but can be overwritten if
      * another kind of Data is needed.
      * @param newValue the new value to set to the DataObject.
      */
     protected void setToData(Object newValue) {
         value.set(newValue,getDataObject());
     }

     /**
      * gets the current value from the data obejct.
      * this method delegates the job to
      * the value object.
      * @return the current value of the data object.
      */
     protected Object getFromData() {
         return value.get(getDataObject());
     }

     /**
      * sets the given value to the UI control
      * @param newValue the value to set to the ui control.
      */
     protected abstract void setToUI(Object newValue);

     /**
      * gets the current value from the UI control.
      * @return the current value from the UI control.
      */
     protected abstract Object getFromUI();

     /**
      * updates the UI control according to the
      * current state of the data object.
      */
     public void updateUI() {
         Object data = getFromData();
         Object ui = getFromUI();
         if (!equals(data, ui))
             try {
                 setToUI(data);
             } catch (Exception ex) {
                 ex.printStackTrace();
                 //TODO tell user...
             }
         enableControls(data);
     }

     /**
      * enables
      * @param currentValue
      */
     protected void enableControls(Object currentValue) {
     }

     /**
      * updates the DataObject according to
      * the current state of the UI control.
      */
     public void updateData() {
         Object data = getFromData();
         Object ui = getFromUI();
         if (!equals(data, ui))
             setToData(ui);
         enableControls(ui);
     }

     public interface Listener {
         public void eventPerformed(Object event);
     }

     /**
      * compares the two given objects.
      * This method is null safe and returns true also if both are null...
      * If both are arrays, treats them as array of short and compares them.
      * @param a first object to compare
      * @param b second object to compare.
      * @return true if both are null or both are equal.
      */
     protected boolean equals(Object a, Object b) {
         if (a == null && b == null)
             return true;
         if (a == null || b == null)
             return false;
         if (a.getClass().isArray()) {
             if (b.getClass().isArray())
                 return Arrays.equals((short[]) a, (short[]) b);
             else
                 return false;
         }
         return a.equals(b);
     }

     /**
      * given a collection containing DataAware objects,
      * calls updateUI() on each memebr of the collection.
      * @param dataAwares a collection containing DataAware objects.
      */
     public static void updateUI(Collection dataAwares) {
         for (Iterator i = dataAwares.iterator(); i.hasNext();)
              ((DataAware) i.next()).updateUI();
     }

     public static void updateData(Collection dataAwares) {
         for (Iterator i = dataAwares.iterator(); i.hasNext();)
              ((DataAware) i.next()).updateData();
     }

     /**
      * /**
      * Given a collection containing DataAware objects,
      * sets the given DataObject to each DataAware object
      * in the given collection
      * @param dataAwares a collection of DataAware objects.
      * @param dataObject new data object to set to the DataAware objects in the given collection.
      * @param updateUI if true, calls updateUI() on each DataAware object.
      */public static void setDataObject(Collection dataAwares, Object dataObject, boolean updateUI) {
         for (Iterator i = dataAwares.iterator(); i.hasNext();)
              ((DataAware) i.next()).setDataObject(dataObject, updateUI);
     }

     /**
      * Value objects read and write a value from and
      * to an object. Typically using reflection and JavaBeans properties
      * or directly using memeber reflection API.
      * DataAware delegates the handling of the DataObject
      * to a Value object.
      * 2 implementations currently exist: PropertyValue,
      * using JavaBeans properties reflection, and DataAwareFields classes
      * which implement different memeber types.
      */
     public interface Value {
         /**
          * gets a value from the given object.
          * @param target the object to get the value from.
          * @return the value from the given object.
          */
         public Object get(Object target);
         /**
          * sets a value to the given object.
          * @param value the value to set to the object.
          * @param target the object to set the value to.
          */
         public void set(Object value, Object target);
         /**
          * checks if this Value object can handle
          * the given object type as a target.
          * @param type the type of a target to check
          * @return true if the given class is acceptible for
          * the Value object. False if not.
          */
         public boolean isAssignable(Class type);
     }

     /**
      * implementation of Value, handling JavaBeans properties through
      * reflection.
      * This Object gets and sets a value a specific
      * (JavaBean-style) property on a given object.
      * @author rp143992
      */
     public static class PropertyValue implements Value {
         /**
          * the get method of the JavaBean-style property
          */
         private Method getMethod;
         /**
          * the set method of the JavaBean-style property
          */
         private Method setMethod;

         /**
          * creates a PropertyValue for the property with
          * the given name, of the given JavaBean object.
          * @param propertyName the property to access. Must be a Cup letter (e.g. PropertyNames.PROPERTY_NAME for getName() and setName("..."). )
          * @param propertyOwner the object which "own" or "contains" the property.
          */
         public PropertyValue(String propertyName, Object propertyOwner) {
             getMethod = createGetMethod(propertyName, propertyOwner);
             setMethod = createSetMethod(propertyName, propertyOwner, getMethod.getReturnType());
         }

         /**
          * called from the constructor, and creates a get method reflection object
          * for the given property and object.
          * @param propName the property name0
          * @param obj the object which contains the property.
          * @return the get method reflection object.
          */
         private static Class[] EMPTY_ARRAY = new Class[0];

         protected Method createGetMethod(String propName, Object obj)
         {
             Method m = null;
             try
             { //try to get a "get" method.

                 m = obj.getClass().getMethod("get" + propName, EMPTY_ARRAY);
             }
             catch (NoSuchMethodException ex1)
             {
                 throw new IllegalArgumentException("get" + propName + "() method does not exist on " + obj.getClass().getName());
             }
             return m;
         }

         /* (non-Javadoc)
          * @see com.sun.star.wizards.ui.event.DataAware.Value#get(java.lang.Object)
          */
         public Object get(Object target) {
             try {
                 return getMethod.invoke(target, EMPTY_ARRAY);
             } catch (IllegalAccessException ex1) {
                 ex1.printStackTrace();
             } catch (InvocationTargetException ex2) {
                 ex2.printStackTrace();
             } catch (NullPointerException npe) {
                 if (getMethod.getReturnType().equals(String.class))
                     return PropertyNames.EMPTY_STRING;
                 if (getMethod.getReturnType().equals(Short.class))
                     return new Short((short) 0);
                 if (getMethod.getReturnType().equals(Integer.class))
                     return 0;
                 if (getMethod.getReturnType().equals(short[].class))
                     return new short[0];
             }
             return null;

         }

         protected Method createSetMethod(String propName, Object obj, Class paramClass) {
             Method m = null;
             try {
                 m = obj.getClass().getMethod("set" + propName, new Class[] { paramClass });
             } catch (NoSuchMethodException ex1) {
                 throw new IllegalArgumentException("set" + propName + "(" + getMethod.getReturnType().getName() + ") method does not exist on " + obj.getClass().getName());
             }
             return m;
         }

         /* (non-Javadoc)
          * @see com.sun.star.wizards.ui.event.DataAware.Value#set(java.lang.Object, java.lang.Object)
          */
         public void set(Object value, Object target) {
             try {
                 setMethod.invoke(target, value);
             } catch (IllegalAccessException ex1) {
                 ex1.printStackTrace();
             } catch (InvocationTargetException ex2) {
                 ex2.printStackTrace();
             }
         }

         /* (non-Javadoc)
          * @see com.sun.star.wizards.ui.event.DataAware.Value#isAssignable(java.lang.Class)
          */
         public boolean isAssignable(Class type) {
             return getMethod.getDeclaringClass().isAssignableFrom(type) &&
                 setMethod.getDeclaringClass().isAssignableFrom(type);
         }
     }
 }
	/**************************************************************
	*
	* 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 com.sun.star.wizards.ui.event;

	import java.lang.reflect.InvocationTargetException;
	import java.lang.reflect.Method;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.Iterator;
	import com.sun.star.wizards.common.PropertyNames;

	/**
	* @author rpiterman
	* DataAware objects are used to live-synchronize UI and DataModel/DataObject.
	* It is used as listener on UI events, to keep the DataObject up to date.
	* This class, as a base abstract class, sets a frame of functionality,
	* delegating the data Object get/set methods to a Value object,
	* and leaving the UI get/set methods abstract.
	* Note that event listenning is not a part of this model.
	* the updateData() or updateUI() methods should be porogramatically called.
	* in child classes, the updateData() will be binded to UI event calls.
	* <br><br>
	* This class holds references to a Data Object and a Value object.
	* The Value object "knows" how to get and set a value from the
	* Data Object.
	*/
	public abstract class DataAware {

	/**
	* this is the data object.
	*/
	protected Object dataObject;
	//protected Method setMethod;
	//protected Method getMethod;
	/**
	* A Value Object knows how to get/set a value
	* from/to the data object.
	*/
	protected Value value;

	/**
	* creates a DataAware object for the given data object and Value object.
	* @param dataObject_
	* @param value_
	*/
	protected DataAware(Object dataObject_, Value value_) {
	dataObject = dataObject_;
	value = value_;
	//getMethod = createGetMethod(dataPropName, dataObject);
	//setMethod = createSetMethod(dataPropName, dataObject, getMethod.getReturnType());
	}

	/**
	* returns the data object.
	* @return
	*/
	public Object getDataObject() {
	return dataObject;
	}

	/**
	* sets a new data object. Optionally
	* update the UI.
	* @param obj the new data object.
	* @param updateUI if true updateUI() will be called.
	*/
	public void setDataObject(Object obj, boolean updateUI) {

	if (obj != null && !value.isAssignable(obj.getClass()))
	throw new ClassCastException("can not cast new DataObject to original Class");

	dataObject = obj;

	if (updateUI)
	updateUI();

	}

	/**
	* Sets the given value to the data object.
	* this method delegates the job to the
	* Value object, but can be overwritten if
	* another kind of Data is needed.
	* @param newValue the new value to set to the DataObject.
	*/
	protected void setToData(Object newValue) {
	value.set(newValue,getDataObject());
	}

	/**
	* gets the current value from the data obejct.
	* this method delegates the job to
	* the value object.
	* @return the current value of the data object.
	*/
	protected Object getFromData() {
	return value.get(getDataObject());
	}

	/**
	* sets the given value to the UI control
	* @param newValue the value to set to the ui control.
	*/
	protected abstract void setToUI(Object newValue);

	/**
	* gets the current value from the UI control.
	* @return the current value from the UI control.
	*/
	protected abstract Object getFromUI();

	/**
	* updates the UI control according to the
	* current state of the data object.
	*/
	public void updateUI() {
	Object data = getFromData();
	Object ui = getFromUI();
	if (!equals(data, ui))
	try {
	setToUI(data);
	} catch (Exception ex) {
	ex.printStackTrace();
	//TODO tell user...
	}
	enableControls(data);
	}

	/**
	* enables
	* @param currentValue
	*/
	protected void enableControls(Object currentValue) {
	}

	/**
	* updates the DataObject according to
	* the current state of the UI control.
	*/
	public void updateData() {
	Object data = getFromData();
	Object ui = getFromUI();
	if (!equals(data, ui))
	setToData(ui);
	enableControls(ui);
	}

	public interface Listener {
	public void eventPerformed(Object event);
	}

	/**
	* compares the two given objects.
	* This method is null safe and returns true also if both are null...
	* If both are arrays, treats them as array of short and compares them.
	* @param a first object to compare
	* @param b second object to compare.
	* @return true if both are null or both are equal.
	*/
	protected boolean equals(Object a, Object b) {
	if (a == null && b == null)
	return true;
	if (a == null \|\| b == null)
	return false;
	if (a.getClass().isArray()) {
	if (b.getClass().isArray())
	return Arrays.equals((short[]) a, (short[]) b);
	else
	return false;
	}
	return a.equals(b);
	}

	/**
	* given a collection containing DataAware objects,
	* calls updateUI() on each memebr of the collection.
	* @param dataAwares a collection containing DataAware objects.
	*/
	public static void updateUI(Collection dataAwares) {
	for (Iterator i = dataAwares.iterator(); i.hasNext();)
	((DataAware) i.next()).updateUI();
	}

	public static void updateData(Collection dataAwares) {
	for (Iterator i = dataAwares.iterator(); i.hasNext();)
	((DataAware) i.next()).updateData();
	}

	/**
	* /**
	* Given a collection containing DataAware objects,
	* sets the given DataObject to each DataAware object
	* in the given collection
	* @param dataAwares a collection of DataAware objects.
	* @param dataObject new data object to set to the DataAware objects in the given collection.
	* @param updateUI if true, calls updateUI() on each DataAware object.
	*/public static void setDataObject(Collection dataAwares, Object dataObject, boolean updateUI) {
	for (Iterator i = dataAwares.iterator(); i.hasNext();)
	((DataAware) i.next()).setDataObject(dataObject, updateUI);
	}

	/**
	* Value objects read and write a value from and
	* to an object. Typically using reflection and JavaBeans properties
	* or directly using memeber reflection API.
	* DataAware delegates the handling of the DataObject
	* to a Value object.
	* 2 implementations currently exist: PropertyValue,
	* using JavaBeans properties reflection, and DataAwareFields classes
	* which implement different memeber types.
	*/
	public interface Value {
	/**
	* gets a value from the given object.
	* @param target the object to get the value from.
	* @return the value from the given object.
	*/
	public Object get(Object target);
	/**
	* sets a value to the given object.
	* @param value the value to set to the object.
	* @param target the object to set the value to.
	*/
	public void set(Object value, Object target);
	/**
	* checks if this Value object can handle
	* the given object type as a target.
	* @param type the type of a target to check
	* @return true if the given class is acceptible for
	* the Value object. False if not.
	*/
	public boolean isAssignable(Class type);
	}

	/**
	* implementation of Value, handling JavaBeans properties through
	* reflection.
	* This Object gets and sets a value a specific
	* (JavaBean-style) property on a given object.
	* @author rp143992
	*/
	public static class PropertyValue implements Value {
	/**
	* the get method of the JavaBean-style property
	*/
	private Method getMethod;
	/**
	* the set method of the JavaBean-style property
	*/
	private Method setMethod;

	/**
	* creates a PropertyValue for the property with
	* the given name, of the given JavaBean object.
	* @param propertyName the property to access. Must be a Cup letter (e.g. PropertyNames.PROPERTY_NAME for getName() and setName("..."). )
	* @param propertyOwner the object which "own" or "contains" the property.
	*/
	public PropertyValue(String propertyName, Object propertyOwner) {
	getMethod = createGetMethod(propertyName, propertyOwner);
	setMethod = createSetMethod(propertyName, propertyOwner, getMethod.getReturnType());
	}

	/**
	* called from the constructor, and creates a get method reflection object
	* for the given property and object.
	* @param propName the property name0
	* @param obj the object which contains the property.
	* @return the get method reflection object.
	*/
	private static Class[] EMPTY_ARRAY = new Class[0];

	protected Method createGetMethod(String propName, Object obj)
	{
	Method m = null;
	try
	{ //try to get a "get" method.

	m = obj.getClass().getMethod("get" + propName, EMPTY_ARRAY);
	}
	catch (NoSuchMethodException ex1)
	{
	throw new IllegalArgumentException("get" + propName + "() method does not exist on " + obj.getClass().getName());
	}
	return m;
	}

	/* (non-Javadoc)
	* @see com.sun.star.wizards.ui.event.DataAware.Value#get(java.lang.Object)
	*/
	public Object get(Object target) {
	try {
	return getMethod.invoke(target, EMPTY_ARRAY);
	} catch (IllegalAccessException ex1) {
	ex1.printStackTrace();
	} catch (InvocationTargetException ex2) {
	ex2.printStackTrace();
	} catch (NullPointerException npe) {
	if (getMethod.getReturnType().equals(String.class))
	return PropertyNames.EMPTY_STRING;
	if (getMethod.getReturnType().equals(Short.class))
	return new Short((short) 0);
	if (getMethod.getReturnType().equals(Integer.class))
	return 0;
	if (getMethod.getReturnType().equals(short[].class))
	return new short[0];
	}
	return null;

	}

	protected Method createSetMethod(String propName, Object obj, Class paramClass) {
	Method m = null;
	try {
	m = obj.getClass().getMethod("set" + propName, new Class[] { paramClass });
	} catch (NoSuchMethodException ex1) {
	throw new IllegalArgumentException("set" + propName + "(" + getMethod.getReturnType().getName() + ") method does not exist on " + obj.getClass().getName());
	}
	return m;
	}

	/* (non-Javadoc)
	* @see com.sun.star.wizards.ui.event.DataAware.Value#set(java.lang.Object, java.lang.Object)
	*/
	public void set(Object value, Object target) {
	try {
	setMethod.invoke(target, value);
	} catch (IllegalAccessException ex1) {
	ex1.printStackTrace();
	} catch (InvocationTargetException ex2) {
	ex2.printStackTrace();
	}
	}

	/* (non-Javadoc)
	* @see com.sun.star.wizards.ui.event.DataAware.Value#isAssignable(java.lang.Class)
	*/
	public boolean isAssignable(Class type) {
	return getMethod.getDeclaringClass().isAssignableFrom(type) &&
	setMethod.getDeclaringClass().isAssignableFrom(type);
	}
	}
	}