package org.hamcrest.beans;

import org.hamcrest.Description;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeMatcher;

/**
 
* A Matcher that checks that an object has a JavaBean property
 
* with the specified name. If an error occurs during introspection
 
* of the object then this is treated as a mismatch.
 
*
 
* @author Iain McGinniss
 
* @author Nat Pryce
 
* @author Steve Freeman
 
*/

public class HasProperty<T> extends TypeSafeMatcher<T> {

    
private final String propertyName;

    
public HasProperty(String propertyName) {
        
this.propertyName = propertyName;
    
}

    
@Override
    
public boolean matchesSafely(T obj) {
        
try {
            
return PropertyUtil.getPropertyDescriptor(propertyName, obj) != null;
        
} catch (IllegalArgumentException e) {
            
return false;
        
}
    
}

    
@Override
    
public void describeMismatchSafely(T item, Description mismatchDescription) {
        
mismatchDescription.appendText("no ").appendValue(propertyName).appendText(" in ").appendValue(item);
    
}

    
@Override
    
public void describeTo(Description description) {
        
description.appendText("hasProperty(").appendValue(propertyName).appendText(")");
    
}

    
/**
     
* Creates a matcher that matches when the examined object has a JavaBean property
     
* with the specified name.
     
* For example:
     
* <pre>assertThat(myBean, hasProperty("foo"))</pre>
     
*
 

     
* @param propertyName
     
*the name of the JavaBean property that examined beans should possess
     
*/

    
public static <T> Matcher<T> hasProperty(String propertyName) {
        
return new HasProperty<T>(propertyName);
    
}

}