OptionConverter.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.log4j.helpers;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.net.URL;
import java.util.Properties;
import org.apache.log4j.Level;
import org.apache.log4j.PropertyConfigurator;
import org.apache.log4j.spi.Configurator;
import org.apache.log4j.spi.LoggerRepository;
// Contributors: Avy Sharell (sharell@online.fr)
// Matthieu Verbert (mve@zurich.ibm.com)
// Colin Sampaleanu
/**
* A convenience class to convert property values to specific types.
*
* @author Ceki Gülcü
* @author Simon Kitching;
* @author Anders Kristensen
*/
public class OptionConverter {
static String DELIM_START = "${";
static char DELIM_STOP = '}';
static int DELIM_START_LEN = 2;
static int DELIM_STOP_LEN = 1;
/**
* OptionConverter is a static class.
*/
private OptionConverter() {
}
public static String[] concatanateArrays(String[] l, String[] r) {
int len = l.length + r.length;
String[] a = new String[len];
System.arraycopy(l, 0, a, 0, l.length);
System.arraycopy(r, 0, a, l.length, r.length);
return a;
}
public static String convertSpecialChars(String s) {
char c;
int len = s.length();
StringBuilder sbuf = new StringBuilder(len);
int i = 0;
while (i < len) {
c = s.charAt(i++);
if (c == '\\') {
c = s.charAt(i++);
if (c == 'n')
c = '\n';
else if (c == 'r')
c = '\r';
else if (c == 't')
c = '\t';
else if (c == 'f')
c = '\f';
else if (c == '\b')
c = '\b';
else if (c == '\"')
c = '\"';
else if (c == '\'')
c = '\'';
else if (c == '\\')
c = '\\';
}
sbuf.append(c);
}
return sbuf.toString();
}
/**
* Very similar to <code>System.getProperty</code> except that the {@link SecurityException} is hidden.
*
* @param key The key to search for.
* @param def The default value to return.
* @return the string value of the system property, or the default value if there is no property with that key.
* @since 1.1
*/
public static String getSystemProperty(String key, String def) {
try {
return System.getProperty(key, def);
} catch (Throwable e) { // MS-Java throws com.ms.security.SecurityExceptionEx
LogLog.debug("Was not allowed to read system property \"" + key + "\".");
return def;
}
}
public static Object instantiateByKey(Properties props, String key, Class superClass, Object defaultValue) {
// Get the value of the property in string form
String className = findAndSubst(key, props);
if (className == null) {
LogLog.error("Could not find value for key " + key);
return defaultValue;
}
// Trim className to avoid trailing spaces that cause problems.
return OptionConverter.instantiateByClassName(className.trim(), superClass, defaultValue);
}
/**
* If <code>value</code> is "true", then <code>true</code> is returned. If
* <code>value</code> is "false", then <code>true</code> is returned. Otherwise,
* <code>default</code> is returned.
*
* <p>
* Case of value is unimportant.
*/
public static boolean toBoolean(String value, boolean dEfault) {
if (value == null)
return dEfault;
String trimmedVal = value.trim();
if ("true".equalsIgnoreCase(trimmedVal))
return true;
if ("false".equalsIgnoreCase(trimmedVal))
return false;
return dEfault;
}
public static int toInt(String value, int dEfault) {
if (value != null) {
String s = value.trim();
try {
return Integer.valueOf(s).intValue();
} catch (NumberFormatException e) {
LogLog.error("[" + s + "] is not in proper int form.");
e.printStackTrace();
}
}
return dEfault;
}
/**
* Converts a standard or custom priority level to a Level object.
* <p>
* If <code>value</code> is of form "level#classname", then the specified class' toLevel method is called to process
* the specified level string; if no '#' character is present, then the default {@link org.apache.log4j.Level} class
* is used to process the level value.
*
* <p>
* As a special case, if the <code>value</code> parameter is equal to the string "NULL", then the value
* <code>null</code> will be returned.
*
* <p>
* If any error occurs while converting the value to a level, the
* <code>defaultValue</code> parameter, which may be <code>null</code>, is
* returned.
*
* <p>
* Case of <code>value</code> is insignificant for the level level, but is significant for the class name part, if
* present.
*
* @since 1.1
*/
public static Level toLevel(String value, Level defaultValue) {
if (value == null)
return defaultValue;
value = value.trim();
int hashIndex = value.indexOf('#');
if (hashIndex == -1) {
if ("NULL".equalsIgnoreCase(value)) {
return null;
} else {
// no class name specified : use standard Level class
return (Level) Level.toLevel(value, defaultValue);
}
}
Level result = defaultValue;
String clazz = value.substring(hashIndex + 1);
String levelName = value.substring(0, hashIndex);
// This is degenerate case but you never know.
if ("NULL".equalsIgnoreCase(levelName)) {
return null;
}
LogLog.debug("toLevel" + ":class=[" + clazz + "]" + ":pri=[" + levelName + "]");
try {
Class customLevel = Loader.loadClass(clazz);
// get a ref to the specified class' static method
// toLevel(String, org.apache.log4j.Level)
Class[] paramTypes = new Class[] { String.class, org.apache.log4j.Level.class };
java.lang.reflect.Method toLevelMethod = customLevel.getMethod("toLevel", paramTypes);
// now call the toLevel method, passing level string + default
Object[] params = new Object[] { levelName, defaultValue };
Object o = toLevelMethod.invoke(null, params);
result = (Level) o;
} catch (ClassNotFoundException e) {
LogLog.warn("custom level class [" + clazz + "] not found.");
} catch (NoSuchMethodException e) {
LogLog.warn("custom level class [" + clazz + "]" + " does not have a class function toLevel(String, Level)",
e);
} catch (java.lang.reflect.InvocationTargetException e) {
if (e.getTargetException() instanceof InterruptedException
|| e.getTargetException() instanceof InterruptedIOException) {
Thread.currentThread().interrupt();
}
LogLog.warn("custom level class [" + clazz + "]" + " could not be instantiated", e);
} catch (ClassCastException e) {
LogLog.warn("class [" + clazz + "] is not a subclass of org.apache.log4j.Level", e);
} catch (IllegalAccessException e) {
LogLog.warn("class [" + clazz + "] cannot be instantiated due to access restrictions", e);
} catch (RuntimeException e) {
LogLog.warn("class [" + clazz + "], level [" + levelName + "] conversion failed.", e);
}
return result;
}
public static long toFileSize(String value, long dEfault) {
if (value == null)
return dEfault;
String s = value.trim().toUpperCase();
long multiplier = 1;
int index;
if ((index = s.indexOf("KB")) != -1) {
multiplier = 1024;
s = s.substring(0, index);
} else if ((index = s.indexOf("MB")) != -1) {
multiplier = 1024 * 1024;
s = s.substring(0, index);
} else if ((index = s.indexOf("GB")) != -1) {
multiplier = 1024 * 1024 * 1024;
s = s.substring(0, index);
}
if (s != null) {
try {
return Long.valueOf(s).longValue() * multiplier;
} catch (NumberFormatException e) {
LogLog.error("[" + s + "] is not in proper int form.");
LogLog.error("[" + value + "] not in expected format.", e);
}
}
return dEfault;
}
/**
* Find the value corresponding to <code>key</code> in <code>props</code>. Then perform variable substitution on the
* found value.
*/
public static String findAndSubst(String key, Properties props) {
String value = props.getProperty(key);
if (value == null)
return null;
try {
return substVars(value, props);
} catch (IllegalArgumentException e) {
LogLog.error("Bad option value [" + value + "].", e);
return value;
}
}
/**
* Instantiate an object given a class name. Check that the
* <code>className</code> is a subclass of <code>superClass</code>. If that test
* fails or the object could not be instantiated, then <code>defaultValue</code> is returned.
*
* @param className The fully qualified class name of the object to instantiate.
* @param superClass The class to which the new object should belong.
* @param defaultValue The object to return in case of non-fulfillment
*/
public static Object instantiateByClassName(String className, Class superClass, Object defaultValue) {
if (className != null) {
try {
Class classObj = Loader.loadClass(className);
if (!superClass.isAssignableFrom(classObj)) {
LogLog.error("A \"" + className + "\" object is not assignable to a \"" + superClass.getName()
+ "\" variable.");
LogLog.error("The class \"" + superClass.getName() + "\" was loaded by ");
LogLog.error("[" + superClass.getClassLoader() + "] whereas object of type ");
LogLog.error("\"" + classObj.getName() + "\" was loaded by [" + classObj.getClassLoader() + "].");
return defaultValue;
}
return classObj.newInstance();
} catch (ClassNotFoundException e) {
LogLog.error("Could not instantiate class [" + className + "].", e);
} catch (IllegalAccessException e) {
LogLog.error("Could not instantiate class [" + className + "].", e);
} catch (InstantiationException e) {
LogLog.error("Could not instantiate class [" + className + "].", e);
} catch (RuntimeException e) {
LogLog.error("Could not instantiate class [" + className + "].", e);
}
}
return defaultValue;
}
/**
* Perform variable substitution in string <code>val</code> from the values of keys found in the system propeties.
*
* <p>
* The variable substitution delimeters are <b>${</b> and <b>}</b>.
*
* <p>
* For example, if the System properties contains "key=value", then the call
*
* <pre>
* String s = OptionConverter.substituteVars("Value of key is ${key}.");
* </pre>
* <p>
* will set the variable <code>s</code> to "Value of key is value.".
*
* <p>
* If no value could be found for the specified key, then the <code>props</code> parameter is searched, if the value
* could not be found there, then substitution defaults to the empty string.
*
* <p>
* For example, if system propeties contains no value for the key "inexistentKey", then the call
*
* <pre>
* String s = OptionConverter.subsVars("Value of inexistentKey is [${inexistentKey}]");
* </pre>
* <p>
* will set <code>s</code> to "Value of inexistentKey is []"
*
* <p>
* An {@link java.lang.IllegalArgumentException} is thrown if <code>val</code> contains a start delimeter "${" which
* is not balanced by a stop delimeter "}".
* </p>
*
* <p>
* <b>Author</b> Avy Sharell</a>
* </p>
*
* @param val The string on which variable substitution is performed.
* @throws IllegalArgumentException if <code>val</code> is malformed.
*/
public static String substVars(String val, Properties props) throws IllegalArgumentException {
StringBuilder sbuf = new StringBuilder();
int i = 0;
int j, k;
while (true) {
j = val.indexOf(DELIM_START, i);
if (j == -1) {
// no more variables
if (i == 0) { // this is a simple string
return val;
} else { // add the tail string which contails no variables and return the result.
sbuf.append(val.substring(i, val.length()));
return sbuf.toString();
}
} else {
sbuf.append(val.substring(i, j));
k = val.indexOf(DELIM_STOP, j);
if (k == -1) {
throw new IllegalArgumentException(
'"' + val + "\" has no closing brace. Opening brace at position " + j + '.');
} else {
j += DELIM_START_LEN;
String key = val.substring(j, k);
// first try in System properties
String replacement = getSystemProperty(key, null);
// then try props parameter
if (replacement == null && props != null) {
replacement = props.getProperty(key);
}
if (replacement != null) {
// Do variable substitution on the replacement string
// such that we can solve "Hello ${x2}" as "Hello p1"
// the where the properties are
// x1=p1
// x2=${x1}
String recursiveReplacement = substVars(replacement, props);
sbuf.append(recursiveReplacement);
}
i = k + DELIM_STOP_LEN;
}
}
}
}
/**
* Configure log4j given an {@link InputStream}.
*
* <p>
* The InputStream will be interpreted by a new instance of a log4j configurator.
* </p>
* <p>
* All configurations steps are taken on the <code>hierarchy</code> passed as a parameter.
* </p>
*
* @param inputStream The configuration input stream.
* @param clazz The class name, of the log4j configurator which will parse the <code>inputStream</code>. This
* must be a subclass of {@link Configurator}, or null. If this value is null then a default
* configurator of {@link PropertyConfigurator} is used.
* @param hierarchy The {@link org.apache.log4j.Hierarchy} to act on.
* @since 1.2.17
*/
static public void selectAndConfigure(InputStream inputStream, String clazz, LoggerRepository hierarchy) {
Configurator configurator = null;
if (clazz != null) {
LogLog.debug("Preferred configurator class: " + clazz);
configurator = (Configurator) instantiateByClassName(clazz, Configurator.class, null);
if (configurator == null) {
LogLog.error("Could not instantiate configurator [" + clazz + "].");
return;
}
} else {
configurator = new PropertyConfigurator();
}
configurator.doConfigure(inputStream, hierarchy);
}
/**
* Configure log4j given a URL.
*
* <p>
* The url must point to a file or resource which will be interpreted by a new instance of a log4j configurator.
*
* <p>
* All configurations steps are taken on the <code>hierarchy</code> passed as a parameter.
*
* <p>
*
* @param url The location of the configuration file or resource.
* @param clazz The classname, of the log4j configurator which will parse the file or resource at
* <code>url</code>. This must be a subclass of {@link Configurator}, or null. If this value is
* null then a default configurator of {@link PropertyConfigurator} is used, unless the filename
* pointed to by <code>url</code> ends in '.xml', in which case
* {@link org.apache.log4j.xml.DOMConfigurator} is used.
* @param hierarchy The {@link org.apache.log4j.Hierarchy} to act on.
* @since 1.1.4
*/
static public void selectAndConfigure(URL url, String clazz, LoggerRepository hierarchy) {
Configurator configurator = null;
String filename = url.getFile();
if (clazz == null && filename != null && filename.endsWith(".xml")) {
clazz = "org.apache.log4j.xml.DOMConfigurator";
}
if (clazz != null) {
LogLog.debug("Preferred configurator class: " + clazz);
configurator = (Configurator) instantiateByClassName(clazz, Configurator.class, null);
if (configurator == null) {
LogLog.error("Could not instantiate configurator [" + clazz + "].");
return;
}
} else {
configurator = new PropertyConfigurator();
}
configurator.doConfigure(url, hierarchy);
}
}