DynaProperty.java
/*
* 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 org.apache.commons.beanutils2;
import java.util.List;
import java.util.Map;
import java.util.Objects;
/**
* <p>
* The metadata describing an individual property of a DynaBean.
* </p>
*
* <p>
* The meta contains an <em>optional</em> content type property ({@link #getContentType}) for use by mapped and iterated properties. A mapped or iterated
* property may choose to indicate the type it expects. The DynaBean implementation may choose to enforce this type on its entries. Alternatively, an
* implementation may choose to ignore this property. All keys for maps must be of type String so no meta data is needed for map keys.
* </p>
*/
public class DynaProperty {
/*
* There are issues with serializing primitive class types on certain JVM versions (including Java 1.3). This class uses a custom serialization
* implementation that writes an integer for these primitive class. This list of constants are the ones used in serialization. If these values are changed,
* then older versions will no longer be read correctly
*/
private static final int BOOLEAN_TYPE = 1;
private static final int BYTE_TYPE = 2;
private static final int CHAR_TYPE = 3;
private static final int DOUBLE_TYPE = 4;
private static final int FLOAT_TYPE = 5;
private static final int INT_TYPE = 6;
private static final int LONG_TYPE = 7;
private static final int SHORT_TYPE = 8;
/**
* Empty array.
*/
public static final DynaProperty[] EMPTY_ARRAY = {};
/** Property name */
protected String name;
/** Property type */
protected transient Class<?> type;
/** The <em>(optional)</em> type of content elements for indexed {@code DynaProperty} */
protected transient Class<?> contentType;
/**
* Constructs a property that accepts any data type.
*
* @param name Name of the property being described
*/
public DynaProperty(final String name) {
this(name, Object.class);
}
/**
* Constructs a property of the specified data type.
*
* @param name Name of the property being described
* @param type Java class representing the property data type
*/
public DynaProperty(final String name, final Class<?> type) {
this.name = name;
this.type = type;
if (type != null && type.isArray()) {
this.contentType = type.getComponentType();
}
}
/**
* Constructs an indexed or mapped {@code DynaProperty} that supports (pseudo)-introspection of the content type.
*
* @param name Name of the property being described
* @param type Java class representing the property data type
* @param contentType Class that all indexed or mapped elements are instances of
*/
public DynaProperty(final String name, final Class<?> type, final Class<?> contentType) {
this.name = name;
this.type = type;
this.contentType = contentType;
}
/**
* Checks this instance against the specified Object for equality. Overrides the default reference test for equality provided by
* {@link Object#equals(Object)}
*
* @param obj The object to compare to
* @return {@code true} if object is a dyna property with the same name type and content type, otherwise {@code false}
* @since 1.8.0
*/
@Override
public boolean equals(final Object obj) {
boolean result;
result = obj == this;
if (!result && obj instanceof DynaProperty) {
final DynaProperty that = (DynaProperty) obj;
result = Objects.equals(this.name, that.name) && Objects.equals(this.type, that.type) && Objects.equals(this.contentType, that.contentType);
}
return result;
}
/**
* Gets the <em>(optional)</em> type of the indexed content for {@code DynaProperty}'s that support this feature.
*
* <p>
* There are issues with serializing primitive class types on certain JVM versions (including Java 1.3). Therefore, this field <strong>must not be
* serialized using the standard methods</strong>.
* </p>
*
* @return the Class for the content type if this is an indexed {@code DynaProperty} and this feature is supported. Otherwise null.
*/
public Class<?> getContentType() {
return contentType;
}
/**
* Gets the name of this property.
*
* @return the name of the property
*/
public String getName() {
return this.name;
}
/**
* <p>
* Gets the Java class representing the data type of the underlying property values.
* </p>
*
* <p>
* There are issues with serializing primitive class types on certain JVM versions (including Java 1.3). Therefore, this field <strong>must not be
* serialized using the standard methods</strong>.
* </p>
*
* <p>
* <strong>Please leave this field as {@code transient}</strong>
* </p>
*
* @return the property type
*/
public Class<?> getType() {
return this.type;
}
/**
* @return the hash code for this dyna property
* @see Object#hashCode
* @since 1.8.0
*/
@Override
public int hashCode() {
int result = 1;
result = result * 31 + (name == null ? 0 : name.hashCode());
result = result * 31 + (type == null ? 0 : type.hashCode());
result = result * 31 + (contentType == null ? 0 : contentType.hashCode());
return result;
}
/**
* Does this property represent an indexed value (ie an array or List)?
*
* @return {@code true} if the property is indexed (i.e. is a List or array), otherwise {@code false}
*/
public boolean isIndexed() {
if (type == null) {
return false;
}
if (type.isArray() || List.class.isAssignableFrom(type)) {
return true;
}
return false;
}
/**
* Does this property represent a mapped value (ie a Map)?
*
* @return {@code true} if the property is a Map otherwise {@code false}
*/
public boolean isMapped() {
if (type == null) {
return false;
}
return Map.class.isAssignableFrom(type);
}
/**
* Gets a String representation of this Object.
*
* @return a String representation of the dyna property
*/
@Override
public String toString() {
final StringBuilder sb = new StringBuilder("DynaProperty[name=");
sb.append(this.name);
sb.append(",type=");
sb.append(this.type);
if (isMapped() || isIndexed()) {
sb.append(" <").append(this.contentType).append(">");
}
sb.append("]");
return sb.toString();
}
}