/**
* 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.hadoop.hbase;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Map.Entry;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.io.util.HeapMemorySizeUtil;
import org.apache.hadoop.hbase.util.VersionInfo;
/**
* Adds HBase configuration files to a Configuration
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class HBaseConfiguration extends Configuration {
private static final Log LOG = LogFactory.getLog(HBaseConfiguration.class);
/**
* Instantinating HBaseConfiguration() is deprecated. Please use
* HBaseConfiguration#create() to construct a plain Configuration
*/
@Deprecated
public HBaseConfiguration() {
//TODO:replace with private constructor, HBaseConfiguration should not extend Configuration
super();
addHbaseResources(this);
LOG.warn("instantiating HBaseConfiguration() is deprecated. Please use"
+ " HBaseConfiguration#create() to construct a plain Configuration");
}
/**
* Instantiating HBaseConfiguration() is deprecated. Please use
* HBaseConfiguration#create(conf) to construct a plain Configuration
*/
@Deprecated
public HBaseConfiguration(final Configuration c) {
//TODO:replace with private constructor
this();
merge(this, c);
}
private static void checkDefaultsVersion(Configuration conf) {
if (conf.getBoolean("hbase.defaults.for.version.skip", Boolean.FALSE)) return;
String defaultsVersion = conf.get("hbase.defaults.for.version");
String thisVersion = VersionInfo.getVersion();
if (!thisVersion.equals(defaultsVersion)) {
throw new RuntimeException(
"hbase-default.xml file seems to be for and old version of HBase (" +
defaultsVersion + "), this version is " + thisVersion);
}
}
public static Configuration addHbaseResources(Configuration conf) {
conf.addResource("hbase-default.xml");
conf.addResource("hbase-site.xml");
checkDefaultsVersion(conf);
HeapMemorySizeUtil.checkForClusterFreeMemoryLimit(conf);
return conf;
}
/**
* Creates a Configuration with HBase resources
*
* @return a Configuration with HBase resources
*/
public static Configuration create() {
Configuration conf = new Configuration();
// In case HBaseConfiguration is loaded from a different classloader than
// Configuration, conf needs to be set with appropriate class loader to resolve
// HBase resources.
conf.setClassLoader(HBaseConfiguration.class.getClassLoader());
return addHbaseResources(conf);
}
/**
* @param that Configuration to clone.
* @return a Configuration created with the hbase-*.xml files plus
* the given configuration.
*/
public static Configuration create(final Configuration that) {
Configuration conf = create();
merge(conf, that);
return conf;
}
/**
* Merge two configurations.
*
* @param destConf the configuration that will be overwritten with items
* from the srcConf
* @param srcConf the source configuration
*/
public static void merge(Configuration destConf, Configuration srcConf) {
for (Entry<String, String> e : srcConf) {
destConf.set(e.getKey(), e.getValue());
}
}
/**
* @return whether to show HBase Configuration in servlet
*/
public static boolean isShowConfInServlet() {
boolean isShowConf = false;
try {
if (Class.forName("org.apache.hadoop.conf.ConfServlet") != null) {
isShowConf = true;
}
} catch (LinkageError e) {
// should we handle it more aggressively in addition to log the error?
LOG.warn("Error thrown: ", e);
} catch (ClassNotFoundException ce) {
LOG.debug("ClassNotFound: ConfServlet");
// ignore
}
return isShowConf;
}
/**
* Get the value of the <code>name</code> property as an <code>int</code>, possibly
* referring to the deprecated name of the configuration property.
* If no such property exists, the provided default value is returned,
* or if the specified value is not a valid <code>int</code>,
* then an error is thrown.
*
* @param name property name.
* @param deprecatedName a deprecatedName for the property to use
* if non-deprecated name is not used
* @param defaultValue default value.
* @return property value as an <code>int</code>,
* or <code>defaultValue</code>.
* @throws NumberFormatException when the value is invalid
*/
// TODO: developer note: This duplicates the functionality of deprecated
// property support in Configuration in Hadoop 2. But since Hadoop-1 does not
// contain these changes, we will do our own as usual. Replace these when H2 is default.
public static int getInt(Configuration conf, String name,
String deprecatedName, int defaultValue) {
if (conf.get(deprecatedName) != null) {
LOG.warn(String.format("Config option \"%s\" is deprecated. Instead, use \"%s\""
, deprecatedName, name));
return conf.getInt(deprecatedName, defaultValue);
} else {
return conf.getInt(name, defaultValue);
}
}
/**
* Get the password from the Configuration instance using the
* getPassword method if it exists. If not, then fall back to the
* general get method for configuration elements.
*
* @param conf configuration instance for accessing the passwords
* @param alias the name of the password element
* @param defPass the default password
* @return String password or default password
* @throws IOException
*/
public static String getPassword(Configuration conf, String alias,
String defPass) throws IOException {
String passwd = null;
try {
Method m = Configuration.class.getMethod("getPassword", String.class);
char[] p = (char[]) m.invoke(conf, alias);
if (p != null) {
LOG.debug(String.format("Config option \"%s\" was found through" +
" the Configuration getPassword method.", alias));
passwd = new String(p);
} else {
LOG.debug(String.format(
"Config option \"%s\" was not found. Using provided default value",
alias));
passwd = defPass;
}
} catch (NoSuchMethodException e) {
// this is a version of Hadoop where the credential
//provider API doesn't exist yet
LOG.debug(String.format(
"Credential.getPassword method is not available." +
" Falling back to configuration."));
passwd = conf.get(alias, defPass);
} catch (SecurityException e) {
throw new IOException(e.getMessage(), e);
} catch (IllegalAccessException e) {
throw new IOException(e.getMessage(), e);
} catch (IllegalArgumentException e) {
throw new IOException(e.getMessage(), e);
} catch (InvocationTargetException e) {
throw new IOException(e.getMessage(), e);
}
return passwd;
}
/**
* For debugging. Dump configurations to system output as xml format.
* Master and RS configurations can also be dumped using
* http services. e.g. "curl http://master:16010/dump"
*/
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
conf.addResource("hbase-site.xml");
conf.set("hbase.defaults.for.version.skip","true");
HBaseConfiguration.create(conf).writeXml(System.out);
//HBaseConfiguration.create().writeXml(System.out);
}
}