FlexiBean.java
/*
* Copyright 2001-present Stephen Colebourne
*
* 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 org.joda.beans.impl.flexi;
import java.io.ObjectStreamException;
import java.io.Serializable;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.regex.Pattern;
import org.joda.beans.DynamicBean;
import org.joda.beans.DynamicMetaBean;
import org.joda.beans.Property;
import org.joda.beans.impl.BasicProperty;
/**
* Implementation of a fully dynamic {@code Bean}.
* <p>
* Properties are dynamic, and can be added and removed at will from the map.
* The internal storage is created lazily to allow a flexi-bean to be used as
* a lightweight extension to another bean.
* <p>
* Each flexi-bean has a different set of properties.
* As such, there is one instance of meta-bean for each flexi-bean.
* <p>
* The keys of a flexi-bean must be simple identifiers as per '[a-zA-z_][a-zA-z0-9_]*'.
*/
public final class FlexiBean implements DynamicBean, Serializable {
// Alternate way to implement this would be to create a list/map of real property
// objects which could then be properly typed
/** Serialization version. */
private static final long serialVersionUID = 1L;
/** Valid regex for keys. */
private static final Pattern VALID_KEY = Pattern.compile("[a-zA-z_][a-zA-z0-9_]*");
/** The meta-bean. */
private final transient FlexiMetaBean metaBean = new FlexiMetaBean(this); // CSIGNORE
/** The underlying data. */
volatile Map<String, Object> data = Collections.emptyMap();// CSIGNORE
//-----------------------------------------------------------------------
/**
* Creates a standalone meta-bean.
* <p>
* This creates a new instance each time in line with dynamic bean principles.
*
* @return the meta-bean, not null
*/
public static DynamicMetaBean meta() {
return new FlexiBean().metaBean();
}
//-----------------------------------------------------------------------
/**
* Constructor.
*/
public FlexiBean() {
}
/**
* Constructor that copies all the data entries from the specified bean.
*
* @param copyFrom the bean to copy from, not null
*/
public FlexiBean(FlexiBean copyFrom) {
putAll(copyFrom.data);
}
// resolve to setup transient field
private Object readResolve() throws ObjectStreamException {
return new FlexiBean(this);
}
//-----------------------------------------------------------------------
/**
* Gets the internal data map.
*
* @return the data, not null
*/
private Map<String, Object> dataWritable() {
if (data == Collections.EMPTY_MAP) {
data = new LinkedHashMap<>();
}
return data;
}
//-----------------------------------------------------------------------
/**
* Gets the number of properties.
*
* @return the number of properties
*/
public int size() {
return data.size();
}
/**
* Checks if the bean contains a specific property.
*
* @param propertyName the property name, null returns false
* @return true if the bean contains the property
*/
public boolean contains(String propertyName) {
return propertyExists(propertyName);
}
/**
* Gets the value of the property.
* <p>
* This returns null if the property does not exist.
*
* @param propertyName the property name, not empty
* @return the value of the property, may be null
*/
public Object get(String propertyName) {
return data.get(propertyName);
}
/**
* Gets the value of the property cast to a specific type.
* <p>
* This returns null if the property does not exist.
*
* @param <T> the value type
* @param propertyName the property name, not empty
* @param type the type to cast to, not null
* @return the value of the property, may be null
* @throws ClassCastException if the type is incorrect
*/
public <T> T get(String propertyName, Class<T> type) {
return type.cast(get(propertyName));
}
/**
* Gets the value of the property as a {@code String}.
* This will use {@link Object#toString()}.
* <p>
* This returns null if the property does not exist.
*
* @param propertyName the property name, not empty
* @return the value of the property, may be null
*/
public String getString(String propertyName) {
Object obj = get(propertyName);
return obj != null ? obj.toString() : null;
}
/**
* Gets the value of the property as a {@code boolean}.
*
* @param propertyName the property name, not empty
* @return the value of the property
* @throws ClassCastException if the value is not compatible
* @throws NullPointerException if the property does not exist or is null
*/
public boolean getBoolean(String propertyName) {
return (Boolean) get(propertyName);
}
/**
* Gets the value of the property as a {@code int}.
*
* @param propertyName the property name, not empty
* @return the value of the property
* @throws ClassCastException if the value is not compatible
* @throws NullPointerException if the property does not exist or is null
*/
public int getInt(String propertyName) {
return ((Number) get(propertyName)).intValue();
}
/**
* Gets the value of the property as a {@code int} using a default value.
*
* @param propertyName the property name, not empty
* @param defaultValue the default value for null or invalid property
* @return the value of the property
* @throws ClassCastException if the value is not compatible
*/
public int getInt(String propertyName, int defaultValue) {
Object obj = get(propertyName);
return obj != null ? ((Number) get(propertyName)).intValue() : defaultValue;
}
/**
* Gets the value of the property as a {@code long}.
*
* @param propertyName the property name, not empty
* @return the value of the property
* @throws ClassCastException if the value is not compatible
* @throws NullPointerException if the property does not exist or is null
*/
public long getLong(String propertyName) {
return ((Number) get(propertyName)).longValue();
}
/**
* Gets the value of the property as a {@code long} using a default value.
*
* @param propertyName the property name, not empty
* @param defaultValue the default value for null or invalid property
* @return the value of the property
* @throws ClassCastException if the value is not compatible
*/
public long getLong(String propertyName, long defaultValue) {
Object obj = get(propertyName);
return obj != null ? ((Number) get(propertyName)).longValue() : defaultValue;
}
/**
* Gets the value of the property as a {@code double}.
*
* @param propertyName the property name, not empty
* @return the value of the property
* @throws ClassCastException if the value is not compatible
* @throws NullPointerException if the property does not exist or is null
*/
public double getDouble(String propertyName) {
return ((Number) get(propertyName)).doubleValue();
}
/**
* Gets the value of the property as a {@code double} using a default value.
*
* @param propertyName the property name, not empty
* @param defaultValue the default value for null or invalid property
* @return the value of the property
* @throws ClassCastException if the value is not compatible
*/
public double getDouble(String propertyName, double defaultValue) {
Object obj = get(propertyName);
return obj != null ? ((Number) get(propertyName)).doubleValue() : defaultValue;
}
//-----------------------------------------------------------------------
/**
* Sets a property in this bean to the specified value.
* <p>
* This creates a property if one does not exist.
*
* @param propertyName the property name, not empty
* @param newValue the new value, may be null
* @return {@code this} for chaining, not null
*/
public FlexiBean append(String propertyName, Object newValue) {
put(propertyName, newValue);
return this;
}
/**
* Sets a property in this bean to the specified value.
* <p>
* This creates a property if one does not exist.
*
* @param propertyName the property name, not empty
* @param newValue the new value, may be null
*/
public void set(String propertyName, Object newValue) {
put(propertyName, newValue);
}
/**
* Sets a property in this bean to the specified value.
* <p>
* This creates a property if one does not exist.
*
* @param propertyName the property name, not empty
* @param newValue the new value, may be null
* @return the old value of the property, may be null
*/
public Object put(String propertyName, Object newValue) {
if (VALID_KEY.matcher(propertyName).matches() == false) {
throw new IllegalArgumentException("Invalid key for FlexiBean: " + propertyName);
}
return dataWritable().put(propertyName, newValue);
}
/**
* Puts the properties in the specified map into this bean.
* <p>
* This creates properties if they do not exist.
*
* @param map the map of properties to add, not null
*/
public void putAll(Map<String, ? extends Object> map) {
if (map.size() > 0) {
for (String key : map.keySet()) {
if (VALID_KEY.matcher(key).matches() == false) {
throw new IllegalArgumentException("Invalid key for FlexiBean: " + key);
}
}
if (data == Collections.EMPTY_MAP) {
data = new LinkedHashMap<>(map);
} else {
data.putAll(map);
}
}
}
/**
* Puts the properties in the specified bean into this bean.
* <p>
* This creates properties if they do not exist.
*
* @param other the map of properties to add, not null
*/
public void putAll(FlexiBean other) {
if (other.size() > 0) {
if (data == Collections.EMPTY_MAP) {
data = new LinkedHashMap<>(other.data);
} else {
data.putAll(other.data);
}
}
}
/**
* Removes a property.
* <p>
* No error occurs if the property does not exist.
*
* @param propertyName the property name, not empty
*/
public void remove(String propertyName) {
propertyRemove(propertyName);
}
/**
* Removes all properties.
*/
public void clear() {
if (data != Collections.EMPTY_MAP) {
data.clear();
}
}
//-----------------------------------------------------------------------
/**
* Checks if the property exists.
*
* @param propertyName the property name, not empty
* @return true if the property exists
*/
public boolean propertyExists(String propertyName) {
return data.containsKey(propertyName);
}
/**
* Gets the value of the property.
*
* @param propertyName the property name, not empty
* @return the value of the property, may be null
*/
public Object propertyGet(String propertyName) {
if (propertyExists(propertyName) == false) {
throw new NoSuchElementException("Unknown property: " + propertyName);
}
return data.get(propertyName);
}
/**
* Sets the value of the property.
*
* @param propertyName the property name, not empty
* @param newValue the new value of the property, may be null
*/
public void propertySet(String propertyName, Object newValue) {
put(propertyName, newValue);
}
//-----------------------------------------------------------------------
@Override
public DynamicMetaBean metaBean() {
return metaBean;
}
@Override
public Property<Object> property(String name) {
return BasicProperty.of(this, FlexiMetaProperty.of(metaBean, name));
}
@Override
public Set<String> propertyNames() {
return data.keySet();
}
@Override
public void propertyDefine(String propertyName, Class<?> propertyType) {
if (propertyExists(propertyName) == false) {
put(propertyName, null);
}
}
@Override
public void propertyRemove(String propertyName) {
if (data != Collections.EMPTY_MAP) {
data.remove(propertyName);
}
}
//-----------------------------------------------------------------------
/**
* Returns a map representing the contents of the bean.
*
* @return a map representing the contents of the bean, not null
*/
public Map<String, Object> toMap() {
if (size() == 0) {
return Collections.emptyMap();
}
return Collections.unmodifiableMap(new LinkedHashMap<>(data));
}
//-----------------------------------------------------------------------
/**
* Clones this bean, returning an independent copy.
*
* @return the clone, not null
*/
@Override
public FlexiBean clone() {
return new FlexiBean(this);
}
/**
* Compares this bean to another based on the property names and content.
*
* @param obj the object to compare to, null returns false
* @return true if equal
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof FlexiBean) {
FlexiBean other = (FlexiBean) obj;
return this.data.equals(other.data);
}
return super.equals(obj);
}
/**
* Returns a suitable hash code.
*
* @return a hash code
*/
@Override
public int hashCode() {
return data.hashCode();
}
/**
* Returns a string that summarises the bean.
* <p>
* The string contains the class name and properties.
*
* @return a summary string, not null
*/
@Override
public String toString() {
return getClass().getSimpleName() + data.toString();
}
}