/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* 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 eu.stratosphere.configuration;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.apache.commons.codec.binary.Base64;
import eu.stratosphere.core.io.IOReadableWritable;
import eu.stratosphere.core.io.StringRecord;
/**
* Lightweight configuration object which can store key/value pairs. Configuration objects
* can be extracted from or integrated into the {@link GlobalConfiguration} object. They can
* be transported via Nephele's IPC system to distribute configuration data at runtime.
* This class is thread-safe.
*
*/
public class Configuration implements IOReadableWritable {
/**
* Stores the concrete key/value pairs of this configuration object.
*/
private Map<String, String> confData = new HashMap<String, String>();
/**
* The class loader to be used for the <code>getClass</code> method.
*/
private ClassLoader classLoader;
/**
* Constructs a new configuration object.
*/
public Configuration() {
this.classLoader = this.getClass().getClassLoader();
}
/**
* Constructs a new configuration object.
*
* @param classLoader
* the class loader to be use for the <code>getClass</code> method
*/
public Configuration(final ClassLoader classLoader) {
this.classLoader = classLoader;
}
/**
* @return the class loader that knows where to locate user classes
*/
public ClassLoader getClassLoader() {
return this.classLoader;
}
/**
* Sets the class loader that knows where to locate user classes
*
* @param classLoader
* the class loader to be use for the <code>getClass</code> method
*/
public void setClassLoader(ClassLoader classLoader) {
this.classLoader = classLoader;
}
// --------------------------------------------------------------------------------------------
/**
* Returns the class associated with the given key as a string.
*
* @param <T>
* the ancestor of both the default value and the potential value
* @param key
* the key pointing to the associated value
* @param defaultValue
* the optional default value returned if no entry exists
* @param ancestor
* the ancestor of both the default value and the potential value
* @return the (default) value associated with the given key
* @throws IllegalStateException
* if the class identified by the associated value cannot be resolved
* @see #setClass(String, Class)
*/
@SuppressWarnings("unchecked")
public <T> Class<T> getClass(String key, Class<? extends T> defaultValue, Class<? super T> ancestor) {
String className = getStringInternal(key);
if (className == null) {
return (Class<T>) defaultValue;
}
try {
return (Class<T>) Class.forName(className, true, this.classLoader);
} catch (ClassNotFoundException e) {
throw new IllegalStateException(e);
}
}
/**
* Returns the class associated with the given key as a string.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
* @throws IllegalStateException
* if the class identified by the associated value cannot be resolved
* @see #setClass(String, Class)
*/
public Class<?> getClass(String key, Class<?> defaultValue) {
return getClass(key, defaultValue, Object.class);
}
/**
* Adds the given key/value pair to the configuration object. The class can be retrieved by invoking
* {@link #getClass(String, Class, Class)} if it is in the scope of the class loader on the caller.
*
* @param key
* the key of the pair to be added
* @param klazz
* the value of the pair to be added
* @see #getClass(String, Class)
* @see #getClass(String, Class, Class)
*/
public void setClass(String key, Class<?> klazz) {
setStringInternal(key, klazz.getName());
}
/**
* Returns the value associated with the given key as a string.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public String getString(String key, String defaultValue) {
String val = getStringInternal(key);
return val == null ? defaultValue : val;
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setString(String key, String value) {
setStringInternal(key, value);
}
/**
* Returns the value associated with the given key as an integer.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public int getInteger(String key, int defaultValue) {
String val = getStringInternal(key);
if (val == null) {
return defaultValue;
} else {
return Integer.parseInt(val);
}
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setInteger(String key, int value) {
setStringInternal(key, Integer.toString(value));
}
/**
* Returns the value associated with the given key as a long.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public long getLong(String key, long defaultValue) {
String val = getStringInternal(key);
if (val == null) {
return defaultValue;
} else {
return Long.parseLong(val);
}
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setLong(String key, long value) {
setStringInternal(key, Long.toString(value));
}
/**
* Returns the value associated with the given key as a boolean.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public boolean getBoolean(String key, boolean defaultValue) {
String val = getStringInternal(key);
if (val == null) {
return defaultValue;
} else {
return Boolean.parseBoolean(val);
}
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setBoolean(final String key, final boolean value) {
setStringInternal(key, Boolean.toString(value));
}
/**
* Returns the value associated with the given key as a float.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public float getFloat(final String key, final float defaultValue) {
String val = getStringInternal(key);
if (val == null) {
return defaultValue;
} else {
return Float.parseFloat(val);
}
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setFloat(String key, float value) {
setStringInternal(key, Float.toString(value));
}
/**
* Returns the value associated with the given key as a double.
*
* @param key
* the key pointing to the associated value
* @param defaultValue
* the default value which is returned in case there is no value associated with the given key
* @return the (default) value associated with the given key
*/
public double getDouble(String key, double defaultValue) {
String val = getStringInternal(key);
if (val == null) {
return defaultValue;
} else {
return Double.parseDouble(val);
}
}
/**
* Adds the given key/value pair to the configuration object.
*
* @param key
* the key of the key/value pair to be added
* @param value
* the value of the key/value pair to be added
*/
public void setDouble(String key, double value) {
setStringInternal(key, Double.toString(value));
}
/**
* Returns the value associated with the given key as a byte array.
*
* @param key
* The key pointing to the associated value.
* @param defaultValue
* The default value which is returned in case there is no value associated with the given key.
* @return the (default) value associated with the given key.
*/
public byte[] getBytes(String key, byte[] defaultValue) {
String encoded = getStringInternal(key);
if (encoded == null) {
return defaultValue;
} else {
return Base64.decodeBase64(encoded.getBytes());
}
}
/**
* Adds the given byte array to the configuration object. If key is <code>null</code> then nothing is added.
*
* @param key
* The key under which the bytes are added.
* @param bytes
* The bytes to be added.
*/
public void setBytes(String key, byte[] bytes) {
String encoded = new String(Base64.encodeBase64(bytes));
setStringInternal(key, encoded);
}
/**
* Returns the keys of all key/value pairs stored inside this
* configuration object.
*
* @return the keys of all key/value pairs stored inside this configuration object
*/
public Set<String> keySet() {
// Copy key set, so return value is independent from the object's internal data structure
final Set<String> retVal = new HashSet<String>();
synchronized (this.confData) {
final Iterator<String> it = this.confData.keySet().iterator();
while (it.hasNext()) {
retVal.add(it.next());
}
}
return retVal;
}
public void addAll(Configuration other) {
synchronized (this.confData) {
synchronized (other.confData) {
this.confData.putAll(other.confData);
}
}
}
/**
* Adds all entries from the given configuration into this configuration. The keys
* are prepended with the given prefix.
*
* @param other
* The configuration whose entries are added to this configuration.
* @param prefix
* The prefix to prepend.
*/
public void addAll(Configuration other, String prefix) {
final StringBuilder bld = new StringBuilder();
bld.append(prefix);
final int pl = bld.length();
synchronized (this.confData) {
synchronized (other.confData) {
for (Map.Entry<String, String> entry : other.confData.entrySet()) {
bld.setLength(pl);
bld.append(entry.getKey());
this.confData.put(bld.toString(), entry.getValue());
}
}
}
}
// --------------------------------------------------------------------------------------------
private String getStringInternal(String key) {
if (key == null) {
throw new NullPointerException("Key must not be null.");
}
synchronized (this.confData) {
return this.confData.get(key);
}
}
private void setStringInternal(String key, String value) {
if (key == null) {
throw new NullPointerException("Key must not be null.");
}
if (value == null) {
throw new NullPointerException("Value must not be null.");
}
synchronized (this.confData) {
this.confData.put(key, value);
}
}
// --------------------------------------------------------------------------------------------
@Override
public void read(final DataInput in) throws IOException {
synchronized (this.confData) {
final int numberOfProperties = in.readInt();
for (int i = 0; i < numberOfProperties; i++) {
final String key = StringRecord.readString(in);
final String value = StringRecord.readString(in);
this.confData.put(key, value);
}
}
}
@Override
public void write(final DataOutput out) throws IOException {
synchronized (this.confData) {
out.writeInt(this.confData.size());
final Iterator<String> it = this.confData.keySet().iterator();
while (it.hasNext()) {
final String key = it.next();
final String value = this.confData.get(key);
StringRecord.writeString(out, key);
StringRecord.writeString(out, value);
}
}
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + confData.hashCode();
return result;
}
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
final Configuration other = (Configuration) obj;
return confData.equals(other.confData);
}
@Override
public String toString() {
return this.confData.toString();
}
}