AbstractPropertyAccessor.java

package org.theonefx.wcframework.ioc;

import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;

import org.theonefx.wcframework.core.TypeConverter;
import org.theonefx.wcframework.core.exception.BeansException;
import org.theonefx.wcframework.core.propertyeditor.PropertyEditorRegistrySupport;
import org.theonefx.wcframework.ioc.exception.InvalidPropertyException;
import org.theonefx.wcframework.ioc.exception.NotWritablePropertyException;
import org.theonefx.wcframework.ioc.exception.NullValueInNestedPathException;
import org.theonefx.wcframework.ioc.exception.PropertyAccessException;
import org.theonefx.wcframework.ioc.exception.PropertyBatchUpdateException;
import org.theonefx.wcframework.ioc.exception.TypeMismatchException;
import org.theonefx.wcframework.ioc.val.MutablePropertyValues;

/**
 * 接口{@link PropertyAccessor}的抽象实现.
 * 提供所有转换方法的基本能实现.
 * 实际的属性访问的实现留给子类.
 */
public abstract class AbstractPropertyAccessor extends PropertyEditorRegistrySupport implements PropertyAccessor, TypeConverter {

	public void setPropertyValue(PropertyValue pv) throws BeansException {
		setPropertyValue(pv.getName(), pv.getValue());
	}

	public void setPropertyValues(PropertyValues pvs) throws BeansException {
		setPropertyValues(pvs, false, false);
	}

	public void setPropertyValues(PropertyValues pvs, boolean ignoreUnknown, boolean ignoreInvalid)
			throws BeansException {

		List<PropertyAccessException> propertyAccessExceptions = null;
		List<PropertyValue> propertyValues = (pvs instanceof MutablePropertyValues ? ((MutablePropertyValues) pvs).getPropertyValueList() : Arrays.asList(pvs.getPropertyValues()));
		for (PropertyValue pv : propertyValues) {
			try {
				// This method may throw any BeansException, 
				// which won't be caught here, 
				// if there is a critical failure such as no matching field.
				// We can attempt to deal only with less serious exceptions.
				setPropertyValue(pv);
			} catch (NotWritablePropertyException ex) {
				if (!ignoreUnknown) {
					throw ex;
				} else {
					// 否则忽略并继续...
				}
			} catch (NullValueInNestedPathException ex) {
				if (!ignoreInvalid) {
					throw ex;
				} else {
					// 否则忽略并继续...
				}
			} catch (PropertyAccessException ex) {
				ex.printStackTrace();
				if (propertyAccessExceptions == null) {
					propertyAccessExceptions = new LinkedList<PropertyAccessException>();
				}
				propertyAccessExceptions.add(ex);
			}
		}

		// If we encountered individual exceptions, throw the composite exception.
		if (propertyAccessExceptions != null) {
			PropertyAccessException[] paeArray = propertyAccessExceptions.toArray(new PropertyAccessException[propertyAccessExceptions.size()]);
			throw new PropertyBatchUpdateException(paeArray);
		}
	}

	public <T> T convertIfNecessary(Object value, Class<T> requiredType) throws TypeMismatchException {
		return convertIfNecessary(value, requiredType, null);
	}

	/**
	 * 获取属性值的真正实现在子类中进行.
	 * @param propertyName 需要被获取值的属性的名称
	 * @return 目标属性的值
	 * @throws InvalidPropertyException 如果找不到该属性或者该属性不可读
	 * @throws PropertyAccessException 如果该属性是有效的，但是对该属性的访问却失败了
	 */
	public abstract Object getPropertyValue(String propertyName) throws BeansException;

	/**
	 * 设置属性值的真正实现在子类中进行.
	 * @param propertyName 需要被设置值的属性的名称
	 * @param value 属性的新的值
	 * @throws InvalidPropertyException 如果找不到该属性或者该属性不可写
	 * @throws PropertyAccessException 该属性本身是有效的，但是调用访问方法时失败或者新的值类型不匹配
	 */
	public abstract void setPropertyValue(String propertyName, Object value) throws BeansException;

}