Coverage Report - org.apache.tapestry.components.IPrimaryKeyConverter
 
Classes in this File Line Coverage Branch Coverage Complexity
IPrimaryKeyConverter
N/A
N/A
1
 
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 // Copyright 2004, 2005 The Apache Software Foundation
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 //
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 // Licensed under the Apache License, Version 2.0 (the "License");
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 // you may not use this file except in compliance with the License.
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 // You may obtain a copy of the License at
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 //
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 //     http://www.apache.org/licenses/LICENSE-2.0
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 //
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 // Unless required by applicable law or agreed to in writing, software
 10  
 // distributed under the License is distributed on an "AS IS" BASIS,
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 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 12  
 // See the License for the specific language governing permissions and
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 // limitations under the License.
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 package org.apache.tapestry.components;
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 17  
 /**
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  * An interface for converting an objects to their primary keys and back.
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  * Typically used to determine how to store a given object as a hidden value
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  * when rendering a form.
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  * <p>
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  * This interface is used by the
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  * {@link org.apache.tapestry.components.ForBean For component}. When a primary
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  * key converter is available, it is used during the render, and as part of the
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  * rewind phase that processes the form submission.
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  * <p>
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  * During rendering, {@link #getPrimaryKey(Object)} is invoked for each value.
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  * This method is invoked just before the For's body is rendered. The resulting
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  * primary key is written into the client as a hidden form field.
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  * <p>
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  * Likewise, during rewind, {@link #getValue(Object)} is invoked for each key,
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  * to get back the same (or equivalent) object. Again, the method is invoked
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  * just before the For's body is rendered.
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  * <p>
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  * The {@link org.apache.tapestry.util.DefaultPrimaryKeyConverter} uses this
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  * relationship between a For component and its primary key converter to track
 37  
  * what the current value being rendered or rewound is.
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  * 
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  * @author mb
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  * @since 4.0
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  */
 42  
 public interface IPrimaryKeyConverter
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 {
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 45  
     /**
 46  
      * Returns the primary key of the given value.
 47  
      * 
 48  
      * @param objValue
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      *            the value for which a primary key needs to be extracted
 50  
      * @return the primary key of the value
 51  
      */
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     Object getPrimaryKey(Object value);
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 54  
     /**
 55  
      * Returns the value corresponding the given primary key.
 56  
      * 
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      * @param objPrimaryKey
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      *            the primary key for which a value needs to be generated
 59  
      * @return the generated value corresponding to the given primary key
 60  
      */
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     Object getValue(Object primaryKey);
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 63  
 }