groovy-core/src/main/groovy/lang/MetaBeanProperty.java

/*
 * Copyright 2003-2007 the original author or authors.
 *
 * Licensed 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 groovy.lang;

import java.lang.reflect.Modifier;

import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;
import org.codehaus.groovy.runtime.MetaClassHelper;

/**
 * Represents a property on a bean which may have a getter and/or a setter
 *
 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
 * @author Pilho Kim
 * @version $Revision$
 */
public class MetaBeanProperty extends MetaProperty {

    private MetaMethod getter;
    private MetaMethod setter;
    private MetaFieldProperty field;

    public MetaBeanProperty(String name, Class type, MetaMethod getter, MetaMethod setter) {
        super(name, type);
        this.getter = getter;
        this.setter = setter;
    }

    /**
     * Get the property of the given object.
     *
     * @param object which to be got
     * @return the property of the given object
     * @throws Exception if the property could not be evaluated
     */
    public Object getProperty(Object object) {
        if (getter == null) {
            //TODO: we probably need a WriteOnlyException class
            throw new GroovyRuntimeException("Cannot read write-only property: " + name);
        }
        return getter.invoke(object, MetaClassHelper.EMPTY_ARRAY);
    }

    /**
     * Set the property on the given object to the new value.
     *
     * @param object   on which to set the property
     * @param newValue the new value of the property
     * @throws RuntimeException if the property could not be set
     */
    public void setProperty(Object object, Object newValue) {
        if (setter == null) {
            throw new GroovyRuntimeException("Cannot set read-only property: " + name);
        }
        newValue = DefaultTypeTransformation.castToType(newValue, getType());
        setter.invoke(object, new Object[]{newValue});
    }

    /**
     * Get the getter method.
     */
    public MetaMethod getGetter() {
        return getter;
    }

    /**
     * Get the setter method.
     */
    public MetaMethod getSetter() {
        return setter;
    }

    /**
     * This is for MetaClass to patch up the object later when looking for get*() methods.
     */
    void setGetter(MetaMethod getter) {
        this.getter = getter;
    }

    /**
     * This is for MetaClass to patch up the object later when looking for set*() methods.
     */
    void setSetter(MetaMethod setter) {
        this.setter = setter;
    }

    public int getModifiers() {
        if (setter != null && getter == null) return setter.getModifiers();
        if (getter != null && setter == null) return getter.getModifiers();
        int modifiers = getter.getModifiers() | setter.getModifiers();
        int visibility = 0;
        if (Modifier.isPublic(modifiers)) visibility = Modifier.PUBLIC;
        if (Modifier.isProtected(modifiers)) visibility = Modifier.PROTECTED;
        if (Modifier.isPrivate(modifiers)) visibility = Modifier.PRIVATE;
        int states = getter.getModifiers() & setter.getModifiers();
        states &= ~(Modifier.PUBLIC | Modifier.PROTECTED | Modifier.PRIVATE);
        states |= visibility;
        return states;
    }

    public void setField(MetaFieldProperty f) {
        this.field = f;
    }

    public MetaFieldProperty getField() {
        return field;
    }
}