FileBasedBuilderParametersImpl.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.builder;
import java.io.File;
import java.net.URL;
import java.util.Map;
import org.apache.commons.configuration2.io.FileHandler;
import org.apache.commons.configuration2.io.FileLocationStrategy;
import org.apache.commons.configuration2.io.FileSystem;
import org.apache.commons.configuration2.io.URLConnectionOptions;
/**
* <p>
* An implementation of {@code BuilderParameters} which contains parameters related to {@code Configuration}
* implementations that are loaded from files.
* </p>
* <p>
* The parameters defined here are interpreted by builder implementations that can deal with file-based configurations.
* Note that these parameters are typically no initialization properties of configuration objects (i.e. they are not
* passed to set methods after the creation of the result configuration). Rather, the parameters object is stored as a
* whole in the builder's map with initialization parameters and can be accessed from there.
* </p>
* <p>
* This class is not thread-safe. It is intended that an instance is constructed and initialized by a single thread
* during configuration of a {@code ConfigurationBuilder}.
* </p>
*
* @since 2.0
*/
public class FileBasedBuilderParametersImpl extends BasicBuilderParameters implements FileBasedBuilderProperties<FileBasedBuilderParametersImpl> {
/** Constant for the key in the parameters map used by this class. */
private static final String PARAM_KEY = RESERVED_PARAMETER_PREFIX + "fileBased";
/** Property name for the reloading refresh delay. */
private static final String PROP_REFRESH_DELAY = "reloadingRefreshDelay";
/** Property name of the reloading detector factory. */
private static final String PROP_DETECTOR_FACTORY = "reloadingDetectorFactory";
/**
* Creates a new {@code FileBasedBuilderParametersImpl} object from the content of the given map. While
* {@code fromParameters()} expects that an object already exists and is stored in the given map, this method creates a
* new instance based on the content of the map. The map can contain properties of a {@code FileHandler} and some
* additional settings which are stored directly in the newly created object. If the map is <b>null</b>, an
* uninitialized instance is returned.
*
* @param map the map with properties (must not be <b>null</b>)
* @return the newly created instance
* @throws ClassCastException if the map contains invalid data
*/
public static FileBasedBuilderParametersImpl fromMap(final Map<String, ?> map) {
final FileBasedBuilderParametersImpl params = new FileBasedBuilderParametersImpl(FileHandler.fromMap(map));
if (map != null) {
params.setReloadingRefreshDelay((Long) map.get(PROP_REFRESH_DELAY));
params.setReloadingDetectorFactory((ReloadingDetectorFactory) map.get(PROP_DETECTOR_FACTORY));
}
return params;
}
/**
* Looks up an instance of this class in the specified parameters map. This is equivalent to
* {@code fromParameters(params, false};}
*
* @param params the map with parameters (must not be <b>null</b>
* @return the instance obtained from the map or <b>null</b>
* @throws IllegalArgumentException if the map is <b>null</b>
*/
public static FileBasedBuilderParametersImpl fromParameters(final Map<String, ?> params) {
return fromParameters(params, false);
}
/**
* Looks up an instance of this class in the specified parameters map and optionally creates a new one if none is found.
* This method can be used to obtain an instance of this class which has been stored in a parameters map. It is
* compatible with the {@code getParameters()} method.
*
* @param params the map with parameters (must not be <b>null</b>
* @param createIfMissing determines the behavior if no instance is found in the map; if <b>true</b>, a new instance
* with default settings is created; if <b>false</b>, <b>null</b> is returned
* @return the instance obtained from the map or <b>null</b>
* @throws IllegalArgumentException if the map is <b>null</b>
*/
public static FileBasedBuilderParametersImpl fromParameters(final Map<String, ?> params, final boolean createIfMissing) {
if (params == null) {
throw new IllegalArgumentException("Parameters map must not be null!");
}
FileBasedBuilderParametersImpl instance = (FileBasedBuilderParametersImpl) params.get(PARAM_KEY);
if (instance == null && createIfMissing) {
instance = new FileBasedBuilderParametersImpl();
}
return instance;
}
/**
* Stores the associated file handler for the location of the configuration.
*/
private FileHandler fileHandler;
/** The factory for reloading detectors. */
private ReloadingDetectorFactory reloadingDetectorFactory;
/** The refresh delay for reloading support. */
private Long reloadingRefreshDelay;
/**
* Creates a new instance of {@code FileBasedBuilderParametersImpl} with an uninitialized {@code FileHandler} object.
*/
public FileBasedBuilderParametersImpl() {
this(null);
}
/**
* Creates a new instance of {@code FileBasedBuilderParametersImpl} and associates it with the given {@code FileHandler}
* object. If the handler is <b>null</b>, a new handler instance is created.
*
* @param handler the associated {@code FileHandler} (can be <b>null</b>)
*/
public FileBasedBuilderParametersImpl(final FileHandler handler) {
fileHandler = handler != null ? handler : new FileHandler();
}
/**
* {@inheritDoc} This implementation also creates a copy of the {@code FileHandler}.
*/
@Override
public FileBasedBuilderParametersImpl clone() {
final FileBasedBuilderParametersImpl copy = (FileBasedBuilderParametersImpl) super.clone();
copy.fileHandler = new FileHandler(fileHandler.getContent(), fileHandler);
return copy;
}
/**
* Gets the {@code FileHandler} managed by this object. This object is updated every time the file location is
* changed.
*
* @return the managed {@code FileHandler}
*/
public FileHandler getFileHandler() {
return fileHandler;
}
/**
* {@inheritDoc} This implementation returns a map which contains this object itself under a specific key. The static
* {@code fromParameters()} method can be used to extract an instance from a parameters map. Of course, the properties
* inherited from the base class are also added to the result map.
*/
@Override
public Map<String, Object> getParameters() {
final Map<String, Object> params = super.getParameters();
params.put(PARAM_KEY, this);
return params;
}
/**
* Gets the {@code ReloadingDetectorFactory}. Result may be <b>null</b> which means that the default factory is to be
* used.
*
* @return the {@code ReloadingDetectorFactory}
*/
public ReloadingDetectorFactory getReloadingDetectorFactory() {
return reloadingDetectorFactory;
}
/**
* Gets the refresh delay for reload operations. Result may be <b>null</b> if this value has not been set.
*
* @return the reloading refresh delay
*/
public Long getReloadingRefreshDelay() {
return reloadingRefreshDelay;
}
/**
* {@inheritDoc} This implementation takes some properties defined in this class into account.
*/
@Override
public void inheritFrom(final Map<String, ?> source) {
super.inheritFrom(source);
final FileBasedBuilderParametersImpl srcParams = fromParameters(source);
if (srcParams != null) {
setFileSystem(srcParams.getFileHandler().getFileSystem());
setLocationStrategy(srcParams.getFileHandler().getLocationStrategy());
if (srcParams.getFileHandler().getEncoding() != null) {
setEncoding(srcParams.getFileHandler().getEncoding());
}
if (srcParams.getReloadingDetectorFactory() != null) {
setReloadingDetectorFactory(srcParams.getReloadingDetectorFactory());
}
if (srcParams.getReloadingRefreshDelay() != null) {
setReloadingRefreshDelay(srcParams.getReloadingRefreshDelay());
}
}
}
@Override
public FileBasedBuilderParametersImpl setBasePath(final String path) {
getFileHandler().setBasePath(path);
return this;
}
@Override
public FileBasedBuilderParametersImpl setEncoding(final String enc) {
getFileHandler().setEncoding(enc);
return this;
}
@Override
public FileBasedBuilderParametersImpl setFile(final File file) {
getFileHandler().setFile(file);
return this;
}
@Override
public FileBasedBuilderParametersImpl setFileName(final String name) {
getFileHandler().setFileName(name);
return this;
}
@Override
public FileBasedBuilderParametersImpl setFileSystem(final FileSystem fs) {
getFileHandler().setFileSystem(fs);
return this;
}
@Override
public FileBasedBuilderParametersImpl setLocationStrategy(final FileLocationStrategy strategy) {
getFileHandler().setLocationStrategy(strategy);
return this;
}
@Override
public FileBasedBuilderParametersImpl setPath(final String path) {
getFileHandler().setPath(path);
return this;
}
@Override
public FileBasedBuilderParametersImpl setReloadingDetectorFactory(final ReloadingDetectorFactory reloadingDetectorFactory) {
this.reloadingDetectorFactory = reloadingDetectorFactory;
return this;
}
@Override
public FileBasedBuilderParametersImpl setReloadingRefreshDelay(final Long reloadingRefreshDelay) {
this.reloadingRefreshDelay = reloadingRefreshDelay;
return this;
}
@Override
public FileBasedBuilderParametersImpl setURL(final URL url) {
getFileHandler().setURL(url);
return this;
}
@Override
public FileBasedBuilderParametersImpl setURL(final URL url, final URLConnectionOptions urlConnectionOptions) {
getFileHandler().setURL(url, urlConnectionOptions);
return this;
}
}