org.apache.juneau.Session Maven / Gradle / Ivy
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// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance *
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// * *
// * 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.juneau;
import static org.apache.juneau.internal.StringUtils.*;
import java.lang.reflect.*;
import java.text.*;
import java.util.*;
import org.apache.juneau.internal.*;
import org.apache.juneau.json.*;
import org.apache.juneau.serializer.*;
/**
* A one-time-use non-thread-safe object that's meant to be used once and then thrown away.
*
*
* Serializers and parsers use session objects to retrieve config properties and to use it as a scratchpad during
* serialize and parse actions.
*/
public abstract class Session {
private JuneauLogger logger;
private final ObjectMap properties;
private Map cache;
private List warnings; // Any warnings encountered.
/**
* Default constructor.
*
* @param args
* Runtime arguments.
*/
protected Session(SessionArgs args) {
this.properties = args.properties == null ? ObjectMap.EMPTY_MAP : args.properties;
}
/**
* Returns true if this session has the specified property defined.
*
* @param key The property key.
* @return true if this session has the specified property defined.
*/
public final boolean hasProperty(String key) {
return properties != null && properties.containsKey(key);
}
/**
* Returns the session property with the specified key.
*
*
* The returned type is the raw value of the property.
*
* @param key The property key.
* @return The session property, or null if the property does not exist.
*/
public final Object getProperty(String key) {
if (properties == null)
return null;
return properties.get(key);
}
/**
* Returns the session property with the specified key and type.
*
* @param key The property key.
* @param type The type to convert the property to.
* @param def The default value if the session property does not exist or is null .
* @return The session property.
*/
@SuppressWarnings("unchecked")
public final T getProperty(String key, Class type, T def) {
if (properties == null)
return def;
type = (Class)ClassUtils.getWrapperIfPrimitive(type);
T t = properties.get(key, type);
return t == null ? def : t;
}
/**
* Same as {@link #getProperty(String, Class, Object)} but allows for more than one default value.
*
* @param key The property key.
* @param type The type to convert the property to.
* @param def
* The default values if the session property does not exist or is null .
* The first non-null value is returned.
* @return The session property.
*/
@SafeVarargs
public final T getProperty(String key, Class type, T...def) {
return getProperty(key, type, ObjectUtils.firstNonNull(def));
}
/**
* Returns the session class property with the specified name.
*
* @param key The property name.
* @param type The class type of the property.
* @param def The default value.
* @return The property value, or the default value if it doesn't exist.
*/
@SuppressWarnings("unchecked")
public final Class getClassProperty(String key, Class type, Class def) {
return getProperty(key, Class.class, def);
}
/**
* Returns an instantiation of the specified class property.
*
* @param key The property name.
* @param type The class type of the property.
* @param def
* The default instance or class to instantiate if the property doesn't exist.
* @return A new property instance.
*/
public T getInstanceProperty(String key, Class type, Object def) {
return newInstance(type, getProperty(key), def);
}
/**
* Returns the specified property as an array of instantiated objects.
*
* @param key The property name.
* @param type The class type of the property.
* @param def The default object to return if the property doesn't exist.
* @return A new property instance.
*/
@SuppressWarnings("unchecked")
public T[] getInstanceArrayProperty(String key, Class type, T[] def) {
Object o = getProperty(key);
T[] t = null;
if (o == null)
t = def;
else if (o.getClass().isArray()) {
if (o.getClass().getComponentType() == type)
t = (T[])o;
else {
t = (T[])Array.newInstance(type, Array.getLength(o));
for (int i = 0; i < Array.getLength(o); i++)
t[i] = newInstance(type, Array.get(o, i), null);
}
} else if (o instanceof Collection) {
Collection c = (Collection)o;
t = (T[])Array.newInstance(type, c.size());
int i = 0;
for (Object o2 : c)
t[i++] = newInstance(type, o2, null);
}
if (t != null)
return t;
throw new ConfigException("Could not instantiate property ''{0}'' as type {1}", key, type);
}
/**
* Returns the session properties.
*
* @return The session properties passed in through the constructor.
*/
protected ObjectMap getProperties() {
return properties;
}
/**
* Returns the session property keys.
*
* @return The session property keys passed in through the constructor.
*/
public Set getPropertyKeys() {
return properties.keySet();
}
@SuppressWarnings("unchecked")
private T newInstance(Class type, Object o, Object def) {
T t = null;
if (o == null) {
if (def == null)
return null;
t = ClassUtils.newInstance(type, def);
}
else if (type.isInstance(o))
t = (T)o;
else if (o.getClass() == Class.class)
t = ClassUtils.newInstance(type, o);
else if (o.getClass() == String.class)
t = ClassUtils.fromString(type, o.toString());
if (t != null)
return t;
throw new ConfigException("Could not instantiate type ''{0}'' as type {1}", o, type);
}
/**
* Adds an arbitrary object to this session's cache.
*
*
* Can be used to store objects for reuse during a session.
*
* @param key The key. Can be any string.
* @param val The cached object.
*/
public final void addToCache(String key, Object val) {
if (cache == null)
cache = new TreeMap<>();
cache.put(key, val);
}
/**
* Adds arbitrary objects to this session's cache.
*
*
* Can be used to store objects for reuse during a session.
*
* @param cacheObjects
* The objects to add to this session's cache.
* No-op if null .
*/
public final void addToCache(Map cacheObjects) {
if (cacheObjects != null) {
if (cache == null)
cache = new TreeMap<>();
cache.putAll(cacheObjects);
}
}
/**
* Returns an object stored in the session cache.
*
* @param c The class type of the object.
* @param key The session object key.
* @return The cached object, or null if it doesn't exist.
*/
@SuppressWarnings("unchecked")
public final T getFromCache(Class c, String key) {
return cache == null ? null : (T)cache.get(key);
}
/**
* Logs a warning message.
*
* @param msg The warning message.
* @param args Optional {@link MessageFormat}-style arguments.
*/
public final void addWarning(String msg, Object... args) {
if (warnings == null)
warnings = new LinkedList<>();
getLogger().warning(msg, args);
warnings.add((warnings.size() + 1) + ": " + format(msg, args));
}
/**
* Returns true if warnings occurred in this session.
*
* @return true if warnings occurred in this session.
*/
public final boolean hasWarnings() {
return warnings != null && warnings.size() > 0;
}
/**
* Returns the warnings that occurred in this session.
*
* @return The warnings that occurred in this session, or null if no warnings occurred.
*/
public final List getWarnings() {
return warnings;
}
/**
* Returns the logger associated with this session.
*
*
* Subclasses can override this method to provide their own logger.
*
* @return The logger associated with this session.
*/
protected final JuneauLogger getLogger() {
if (logger == null)
logger = JuneauLogger.getLogger(getClass());
return logger;
}
/**
* Returns the properties defined on this bean context as a simple map for debugging purposes.
*
* @return A new map containing the properties defined on this context.
*/
public ObjectMap asMap() {
return new ObjectMap();
}
@Override /* Object */
public String toString() {
try {
return asMap().toString(SimpleJsonSerializer.DEFAULT_READABLE);
} catch (SerializeException e) {
return e.getLocalizedMessage();
}
}
/**
* Throws a {@link BeanRuntimeException} if any warnings occurred in this session.
*/
public void checkForWarnings() {
if (warnings != null && ! warnings.isEmpty())
throw new BeanRuntimeException("Warnings occurred in session: \n" + join(getWarnings(), "\n"));
}
}