ConfigurationDynaBean.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.configuration2.beanutils;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.List;
import java.util.Objects;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.DynaClass;
import org.apache.commons.configuration2.Configuration;
import org.apache.commons.configuration2.ConfigurationMap;
import org.apache.commons.configuration2.SubsetConfiguration;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* The {@code ConfigurationDynaBean} dynamically reads and writes configurations properties from a wrapped
* configuration-collection {@link org.apache.commons.configuration2.Configuration} instance. It also implements a
* {@link java.util.Map} interface so that it can be used in JSP 2.0 Expression Language expressions.
*
* <p>
* The {@code ConfigurationDynaBean} maps nested and mapped properties to the appropriate {@code Configuration} subset
* using the {@link org.apache.commons.configuration2.Configuration#subset} method. Similarly, indexed properties
* reference lists of configuration properties using the
* {@link org.apache.commons.configuration2.Configuration#getList(String)} method. Setting an indexed property is
* supported, too.
* </p>
*
* <p>
* Note: Some of the methods expect that a dot (".") is used as property delimiter for the wrapped
* configuration. This is true for most of the default configurations. Hierarchical configurations, for which a specific
* expression engine is set, may cause problems.
* </p>
*
* @since 1.0-rc1
*/
public class ConfigurationDynaBean extends ConfigurationMap implements DynaBean {
/** Constant for the property delimiter. */
private static final String PROPERTY_DELIMITER = ".";
/** The logger. */
private static final Log LOG = LogFactory.getLog(ConfigurationDynaBean.class);
/**
* Constructs a new instance of {@code ConfigurationDynaBean} and sets the configuration this bean is associated with.
*
* @param configuration the configuration
*/
public ConfigurationDynaBean(final Configuration configuration) {
super(configuration);
if (LOG.isTraceEnabled()) {
LOG.trace("ConfigurationDynaBean(" + configuration + ")");
}
}
/**
* Checks whether the given name references an indexed property. This implementation tests for properties of type list or
* array. If the property does not exist, an exception is thrown.
*
* @param name the name of the property to check
* @return a flag whether this is an indexed property
* @throws IllegalArgumentException if the property does not exist
*/
private boolean checkIndexedProperty(final String name) {
final Object property = getConfiguration().getProperty(name);
if (property == null) {
throw new IllegalArgumentException("Property '" + name + "' does not exist.");
}
return property instanceof List || property.getClass().isArray();
}
@Override
public boolean contains(final String name, final String key) {
final Configuration subset = getConfiguration().subset(name);
if (subset == null) {
throw new IllegalArgumentException("Mapped property '" + name + "' does not exist.");
}
return subset.containsKey(key);
}
@Override
public Object get(final String name) {
if (LOG.isTraceEnabled()) {
LOG.trace("get(" + name + ")");
}
// get configuration property
Object result = getConfiguration().getProperty(name);
if (result == null) {
// otherwise attempt to create bean from configuration subset
final Configuration subset = new SubsetConfiguration(getConfiguration(), name, PROPERTY_DELIMITER);
if (!subset.isEmpty()) {
result = new ConfigurationDynaBean(subset);
}
}
if (LOG.isDebugEnabled()) {
LOG.debug(name + "=[" + result + "]");
}
if (result == null) {
throw new IllegalArgumentException("Property '" + name + "' does not exist.");
}
return result;
}
@Override
public Object get(final String name, final int index) {
if (!checkIndexedProperty(name)) {
throw new IllegalArgumentException("Property '" + name + "' is not indexed.");
}
final List<Object> list = getConfiguration().getList(name);
return list.get(index);
}
@Override
public Object get(final String name, final String key) {
final Configuration subset = getConfiguration().subset(name);
if (subset == null) {
throw new IllegalArgumentException("Mapped property '" + name + "' does not exist.");
}
return subset.getProperty(key);
}
@Override
public DynaClass getDynaClass() {
return new ConfigurationDynaClass(getConfiguration());
}
@Override
public void remove(final String name, final String key) {
final Configuration subset = new SubsetConfiguration(getConfiguration(), name, PROPERTY_DELIMITER);
subset.setProperty(key, null);
}
@Override
public void set(final String name, final int index, final Object value) {
if (!checkIndexedProperty(name) && index > 0) {
throw new IllegalArgumentException("Property '" + name + "' is not indexed.");
}
final Object property = getConfiguration().getProperty(name);
if (property instanceof List) {
// This is safe because multiple values of a configuration property
// are always stored as lists of type Object.
@SuppressWarnings("unchecked")
final List<Object> list = (List<Object>) property;
list.set(index, value);
getConfiguration().setProperty(name, list);
} else if (property.getClass().isArray()) {
Array.set(property, index, value);
} else if (index == 0) {
getConfiguration().setProperty(name, value);
}
}
@Override
public void set(final String name, final Object value) {
if (LOG.isTraceEnabled()) {
LOG.trace("set(" + name + "," + value + ")");
}
Objects.requireNonNull(value, "value");
if (value instanceof Collection) {
final Collection<?> collection = (Collection<?>) value;
collection.forEach(v -> getConfiguration().addProperty(name, v));
} else if (value.getClass().isArray()) {
final int length = Array.getLength(value);
for (int i = 0; i < length; i++) {
getConfiguration().addProperty(name, Array.get(value, i));
}
} else {
getConfiguration().setProperty(name, value);
}
}
@Override
public void set(final String name, final String key, final Object value) {
getConfiguration().setProperty(name + "." + key, value);
}
}