/*
* 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.configuration;
import java.awt.Color;
import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.net.InetAddress;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.UnknownHostException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import org.apache.commons.collections.IteratorUtils;
import org.apache.commons.collections.iterators.IteratorChain;
import org.apache.commons.collections.iterators.SingletonIterator;
import org.apache.commons.lang.BooleanUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.SystemUtils;
/**
* A utility class to convert the configuration properties into any type.
*
* @author Emmanuel Bourg
* @version $Revision: 1034102 $, $Date: 2010-11-11 21:28:05 +0100 (Do, 11. Nov 2010) $
* @since 1.1
*/
public final class PropertyConverter
{
/** Constant for the list delimiter as char.*/
static final char LIST_ESC_CHAR = '\\';
/** Constant for the list delimiter escaping character as string.*/
static final String LIST_ESCAPE = String.valueOf(LIST_ESC_CHAR);
/** Constant for the prefix of hex numbers.*/
private static final String HEX_PREFIX = "0x";
/** Constant for the radix of hex numbers.*/
private static final int HEX_RADIX = 16;
/** Constant for the Java version 1.5.*/
private static final float JAVA_VERSION_1_5 = 1.5f;
/** Constant for the argument classes of the Number constructor that takes a String. */
private static final Class[] CONSTR_ARGS = {String.class};
/** The fully qualified name of {@link javax.mail.internet.InternetAddress} */
private static final String INTERNET_ADDRESS_CLASSNAME = "javax.mail.internet.InternetAddress";
/**
* Private constructor prevents instances from being created.
*/
private PropertyConverter()
{
// to prevent instanciation...
}
/**
* Converts the specified value to the target class. If the class is a
* primitive type (Integer.TYPE, Boolean.TYPE, etc) the value returned
* will use the wrapper type (Integer.class, Boolean.class, etc).
*
* @param cls the target class of the converted value
* @param value the value to convert
* @param params optional parameters used for the conversion
* @return the converted value
* @throws ConversionException if the value is not compatible with the requested type
*
* @since 1.5
*/
static Object to(Class cls, Object value, Object[] params) throws ConversionException
{
if (Boolean.class.equals(cls) || Boolean.TYPE.equals(cls))
{
return toBoolean(value);
}
else if (Number.class.isAssignableFrom(cls) || cls.isPrimitive())
{
if (Integer.class.equals(cls) || Integer.TYPE.equals(cls))
{
return toInteger(value);
}
else if (Long.class.equals(cls) || Long.TYPE.equals(cls))
{
return toLong(value);
}
else if (Byte.class.equals(cls) || Byte.TYPE.equals(cls))
{
return toByte(value);
}
else if (Short.class.equals(cls) || Short.TYPE.equals(cls))
{
return toShort(value);
}
else if (Float.class.equals(cls) || Float.TYPE.equals(cls))
{
return toFloat(value);
}
else if (Double.class.equals(cls) || Double.TYPE.equals(cls))
{
return toDouble(value);
}
else if (BigInteger.class.equals(cls))
{
return toBigInteger(value);
}
else if (BigDecimal.class.equals(cls))
{
return toBigDecimal(value);
}
}
else if (Date.class.equals(cls))
{
return toDate(value, (String) params[0]);
}
else if (Calendar.class.equals(cls))
{
return toCalendar(value, (String) params[0]);
}
else if (URL.class.equals(cls))
{
return toURL(value);
}
else if (Locale.class.equals(cls))
{
return toLocale(value);
}
else if (isEnum(cls))
{
return toEnum(value, cls);
}
else if (Color.class.equals(cls))
{
return toColor(value);
}
else if (cls.getName().equals(INTERNET_ADDRESS_CLASSNAME))
{
return toInternetAddress(value);
}
else if (InetAddress.class.isAssignableFrom(cls))
{
return toInetAddress(value);
}
throw new ConversionException("The value '" + value + "' (" + value.getClass() + ")"
+ " can't be converted to a " + cls.getName() + " object");
}
/**
* Convert the specified object into a Boolean. Internally the
* <code>org.apache.commons.lang.BooleanUtils</code> class from the
* <a href="http://commons.apache.org/lang/">Commons Lang</a>
* project is used to perform this conversion. This class accepts some more
* tokens for the boolean value of <b>true</b>, e.g. <code>yes</code> and
* <code>on</code>. Please refer to the documentation of this class for more
* details.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a boolean
*/
public static Boolean toBoolean(Object value) throws ConversionException
{
if (value instanceof Boolean)
{
return (Boolean) value;
}
else if (value instanceof String)
{
Boolean b = BooleanUtils.toBooleanObject((String) value);
if (b == null)
{
throw new ConversionException("The value " + value + " can't be converted to a Boolean object");
}
return b;
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Boolean object");
}
}
/**
* Convert the specified object into a Byte.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a byte
*/
public static Byte toByte(Object value) throws ConversionException
{
Number n = toNumber(value, Byte.class);
if (n instanceof Byte)
{
return (Byte) n;
}
else
{
return new Byte(n.byteValue());
}
}
/**
* Convert the specified object into a Short.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a short
*/
public static Short toShort(Object value) throws ConversionException
{
Number n = toNumber(value, Short.class);
if (n instanceof Short)
{
return (Short) n;
}
else
{
return new Short(n.shortValue());
}
}
/**
* Convert the specified object into an Integer.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to an integer
*/
public static Integer toInteger(Object value) throws ConversionException
{
Number n = toNumber(value, Integer.class);
if (n instanceof Integer)
{
return (Integer) n;
}
else
{
return new Integer(n.intValue());
}
}
/**
* Convert the specified object into a Long.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Long
*/
public static Long toLong(Object value) throws ConversionException
{
Number n = toNumber(value, Long.class);
if (n instanceof Long)
{
return (Long) n;
}
else
{
return new Long(n.longValue());
}
}
/**
* Convert the specified object into a Float.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Float
*/
public static Float toFloat(Object value) throws ConversionException
{
Number n = toNumber(value, Float.class);
if (n instanceof Float)
{
return (Float) n;
}
else
{
return new Float(n.floatValue());
}
}
/**
* Convert the specified object into a Double.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Double
*/
public static Double toDouble(Object value) throws ConversionException
{
Number n = toNumber(value, Double.class);
if (n instanceof Double)
{
return (Double) n;
}
else
{
return new Double(n.doubleValue());
}
}
/**
* Convert the specified object into a BigInteger.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a BigInteger
*/
public static BigInteger toBigInteger(Object value) throws ConversionException
{
Number n = toNumber(value, BigInteger.class);
if (n instanceof BigInteger)
{
return (BigInteger) n;
}
else
{
return BigInteger.valueOf(n.longValue());
}
}
/**
* Convert the specified object into a BigDecimal.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a BigDecimal
*/
public static BigDecimal toBigDecimal(Object value) throws ConversionException
{
Number n = toNumber(value, BigDecimal.class);
if (n instanceof BigDecimal)
{
return (BigDecimal) n;
}
else
{
return new BigDecimal(n.doubleValue());
}
}
/**
* Tries to convert the specified object into a number object. This method
* is used by the conversion methods for number types. Note that the return
* value is not in always of the specified target class, but only if a new
* object has to be created.
*
* @param value the value to be converted (must not be <b>null</b>)
* @param targetClass the target class of the conversion (must be derived
* from <code>java.lang.Number</code>)
* @return the converted number
* @throws ConversionException if the object cannot be converted
*/
static Number toNumber(Object value, Class targetClass) throws ConversionException
{
if (value instanceof Number)
{
return (Number) value;
}
else
{
String str = value.toString();
if (str.startsWith(HEX_PREFIX))
{
try
{
return new BigInteger(str.substring(HEX_PREFIX.length()), HEX_RADIX);
}
catch (NumberFormatException nex)
{
throw new ConversionException("Could not convert " + str
+ " to " + targetClass.getName()
+ "! Invalid hex number.", nex);
}
}
try
{
Constructor constr = targetClass.getConstructor(CONSTR_ARGS);
return (Number) constr.newInstance(new Object[]{str});
}
catch (InvocationTargetException itex)
{
throw new ConversionException("Could not convert " + str
+ " to " + targetClass.getName(), itex
.getTargetException());
}
catch (Exception ex)
{
// Treat all possible exceptions the same way
throw new ConversionException(
"Conversion error when trying to convert " + str
+ " to " + targetClass.getName(), ex);
}
}
}
/**
* Convert the specified object into an URL.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to an URL
*/
public static URL toURL(Object value) throws ConversionException
{
if (value instanceof URL)
{
return (URL) value;
}
else if (value instanceof String)
{
try
{
return new URL((String) value);
}
catch (MalformedURLException e)
{
throw new ConversionException("The value " + value + " can't be converted to an URL", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to an URL");
}
}
/**
* Convert the specified object into a Locale.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Locale
*/
public static Locale toLocale(Object value) throws ConversionException
{
if (value instanceof Locale)
{
return (Locale) value;
}
else if (value instanceof String)
{
List elements = split((String) value, '_');
int size = elements.size();
if (size >= 1 && (((String) elements.get(0)).length() == 2 || ((String) elements.get(0)).length() == 0))
{
String language = (String) elements.get(0);
String country = (String) ((size >= 2) ? elements.get(1) : "");
String variant = (String) ((size >= 3) ? elements.get(2) : "");
return new Locale(language, country, variant);
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Locale");
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Locale");
}
}
/**
* Split a string on the specified delimiter. To be removed when
* commons-lang has a better replacement available (Tokenizer?).
*
* todo: replace with a commons-lang equivalent
*
* @param s the string to split
* @param delimiter the delimiter
* @param trim a flag whether the single elements should be trimmed
* @return a list with the single tokens
*/
public static List split(String s, char delimiter, boolean trim)
{
if (s == null)
{
return new ArrayList();
}
List list = new ArrayList();
StringBuffer token = new StringBuffer();
int begin = 0;
boolean inEscape = false;
while (begin < s.length())
{
char c = s.charAt(begin);
if (inEscape)
{
// last character was the escape marker
// can current character be escaped?
if (c != delimiter && c != LIST_ESC_CHAR)
{
// no, also add escape character
token.append(LIST_ESC_CHAR);
}
token.append(c);
inEscape = false;
}
else
{
if (c == delimiter)
{
// found a list delimiter -> add token and resetDefaultFileSystem buffer
String t = token.toString();
if (trim)
{
t = t.trim();
}
list.add(t);
token = new StringBuffer();
}
else if (c == LIST_ESC_CHAR)
{
// eventually escape next character
inEscape = true;
}
else
{
token.append(c);
}
}
begin++;
}
// Trailing delimiter?
if (inEscape)
{
token.append(LIST_ESC_CHAR);
}
// Add last token
String t = token.toString();
if (trim)
{
t = t.trim();
}
list.add(t);
return list;
}
/**
* Split a string on the specified delimiter always trimming the elements.
* This is a shortcut for <code>split(s, delimiter, true)</code>.
*
* @param s the string to split
* @param delimiter the delimiter
* @return a list with the single tokens
*/
public static List split(String s, char delimiter)
{
return split(s, delimiter, true);
}
/**
* Escapes the delimiters that might be contained in the given string. This
* method works like {@link #escapeListDelimiter(String, char)}. In addition,
* a single backslash will also be escaped.
*
* @param s the string with the value
* @param delimiter the list delimiter to use
* @return the correctly escaped string
*/
public static String escapeDelimiters(String s, char delimiter)
{
String s1 = StringUtils.replace(s, LIST_ESCAPE, LIST_ESCAPE + LIST_ESCAPE);
return escapeListDelimiter(s1, delimiter);
}
/**
* Escapes the list delimiter if it is contained in the given string. This
* method ensures that list delimiter characters that are part of a
* property's value are correctly escaped when a configuration is saved to a
* file. Otherwise when loaded again the property will be treated as a list
* property.
*
* @param s the string with the value
* @param delimiter the list delimiter to use
* @return the escaped string
* @since 1.7
*/
public static String escapeListDelimiter(String s, char delimiter)
{
return StringUtils.replace(s, String.valueOf(delimiter), LIST_ESCAPE
+ delimiter);
}
/**
* Convert the specified object into a Color. If the value is a String,
* the format allowed is (#)?[0-9A-F]{6}([0-9A-F]{2})?. Examples:
* <ul>
* <li>FF0000 (red)</li>
* <li>0000FFA0 (semi transparent blue)</li>
* <li>#CCCCCC (gray)</li>
* <li>#00FF00A0 (semi transparent green)</li>
* </ul>
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Color
*/
public static Color toColor(Object value) throws ConversionException
{
if (value instanceof Color)
{
return (Color) value;
}
else if (value instanceof String && !StringUtils.isBlank((String) value))
{
String color = ((String) value).trim();
int[] components = new int[3];
// check the size of the string
int minlength = components.length * 2;
if (color.length() < minlength)
{
throw new ConversionException("The value " + value + " can't be converted to a Color");
}
// remove the leading #
if (color.startsWith("#"))
{
color = color.substring(1);
}
try
{
// parse the components
for (int i = 0; i < components.length; i++)
{
components[i] = Integer.parseInt(color.substring(2 * i, 2 * i + 2), HEX_RADIX);
}
// parse the transparency
int alpha;
if (color.length() >= minlength + 2)
{
alpha = Integer.parseInt(color.substring(minlength, minlength + 2), HEX_RADIX);
}
else
{
alpha = Color.black.getAlpha();
}
return new Color(components[0], components[1], components[2], alpha);
}
catch (Exception e)
{
throw new ConversionException("The value " + value + " can't be converted to a Color", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Color");
}
}
/**
* Convert the specified value into an internet address.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a InetAddress
*
* @since 1.5
*/
static InetAddress toInetAddress(Object value) throws ConversionException
{
if (value instanceof InetAddress)
{
return (InetAddress) value;
}
else if (value instanceof String)
{
try
{
return InetAddress.getByName((String) value);
}
catch (UnknownHostException e)
{
throw new ConversionException("The value " + value + " can't be converted to a InetAddress", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a InetAddress");
}
}
/**
* Convert the specified value into an email address.
*
* @param value the value to convert
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to an email address
*
* @since 1.5
*/
static Object toInternetAddress(Object value) throws ConversionException
{
if (value.getClass().getName().equals(INTERNET_ADDRESS_CLASSNAME))
{
return value;
}
else if (value instanceof String)
{
try
{
Constructor ctor = Class.forName(INTERNET_ADDRESS_CLASSNAME).getConstructor(new Class[] {String.class});
return ctor.newInstance(new Object[] {value});
}
catch (Exception e)
{
throw new ConversionException("The value " + value + " can't be converted to a InternetAddress", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a InternetAddress");
}
}
/**
* Calls Class.isEnum() on Java 5, returns false on older JRE.
*/
static boolean isEnum(Class cls)
{
if (!SystemUtils.isJavaVersionAtLeast(JAVA_VERSION_1_5))
{
return false;
}
try
{
Method isEnumMethod = Class.class.getMethod("isEnum", new Class[] {});
return ((Boolean) isEnumMethod.invoke(cls, new Object[] {})).booleanValue();
}
catch (Exception e)
{
// impossible
throw new RuntimeException(e.getMessage());
}
}
/**
* Convert the specified value into a Java 5 enum.
*
* @param value the value to convert
* @param cls the type of the enumeration
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to an enumeration
*
* @since 1.5
*/
static Object toEnum(Object value, Class cls) throws ConversionException
{
if (value.getClass().equals(cls))
{
return value;
}
else if (value instanceof String)
{
try
{
Method valueOfMethod = cls.getMethod("valueOf", new Class[] {String.class});
return valueOfMethod.invoke(null, new Object[] {value});
}
catch (Exception e)
{
throw new ConversionException("The value " + value + " can't be converted to a " + cls.getName());
}
}
else if (value instanceof Number)
{
try
{
Method valuesMethod = cls.getMethod("values", new Class[] {});
Object valuesArray = valuesMethod.invoke(null, new Object[] {});
return Array.get(valuesArray, ((Number) value).intValue());
}
catch (Exception e)
{
throw new ConversionException("The value " + value + " can't be converted to a " + cls.getName());
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a " + cls.getName());
}
}
/**
* Convert the specified object into a Date.
*
* @param value the value to convert
* @param format the DateFormat pattern to parse String values
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Calendar
*/
public static Date toDate(Object value, String format) throws ConversionException
{
if (value instanceof Date)
{
return (Date) value;
}
else if (value instanceof Calendar)
{
return ((Calendar) value).getTime();
}
else if (value instanceof String)
{
try
{
return new SimpleDateFormat(format).parse((String) value);
}
catch (ParseException e)
{
throw new ConversionException("The value " + value + " can't be converted to a Date", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Date");
}
}
/**
* Convert the specified object into a Calendar.
*
* @param value the value to convert
* @param format the DateFormat pattern to parse String values
* @return the converted value
* @throws ConversionException thrown if the value cannot be converted to a Calendar
*/
public static Calendar toCalendar(Object value, String format) throws ConversionException
{
if (value instanceof Calendar)
{
return (Calendar) value;
}
else if (value instanceof Date)
{
Calendar calendar = Calendar.getInstance();
calendar.setTime((Date) value);
return calendar;
}
else if (value instanceof String)
{
try
{
Calendar calendar = Calendar.getInstance();
calendar.setTime(new SimpleDateFormat(format).parse((String) value));
return calendar;
}
catch (ParseException e)
{
throw new ConversionException("The value " + value + " can't be converted to a Calendar", e);
}
}
else
{
throw new ConversionException("The value " + value + " can't be converted to a Calendar");
}
}
/**
* Return an iterator over the simple values of a composite value. The value
* specified is handled depending on its type:
* <ul>
* <li>Strings are checked for delimiter characters and splitted if necessary.</li>
* <li>For collections the single elements are checked.</li>
* <li>Arrays are treated like collections.</li>
* <li>All other types are directly inserted.</li>
* <li>Recursive combinations are supported, e.g. a collection containing array that contain strings.</li>
* </ul>
*
* @param value the value to "split"
* @param delimiter the delimiter for String values
* @return an iterator for accessing the single values
*/
public static Iterator toIterator(Object value, char delimiter)
{
if (value == null)
{
return IteratorUtils.emptyIterator();
}
if (value instanceof String)
{
String s = (String) value;
if (s.indexOf(delimiter) > 0)
{
return split((String) value, delimiter).iterator();
}
else
{
return new SingletonIterator(value);
}
}
else if (value instanceof Collection)
{
return toIterator(((Collection) value).iterator(), delimiter);
}
else if (value.getClass().isArray())
{
return toIterator(IteratorUtils.arrayIterator(value), delimiter);
}
else if (value instanceof Iterator)
{
Iterator iterator = (Iterator) value;
IteratorChain chain = new IteratorChain();
while (iterator.hasNext())
{
chain.addIterator(toIterator(iterator.next(), delimiter));
}
return chain;
}
else
{
return new SingletonIterator(value);
}
}
/**
* Performs interpolation of the specified value. This method checks if the
* given value contains variables of the form <code>${...}</code>. If
* this is the case, all occurrances will be substituted by their current
* values.
*
* @param value the value to be interpolated
* @param config the current configuration object
* @return the interpolated value
*/
public static Object interpolate(Object value, AbstractConfiguration config)
{
if (value instanceof String)
{
return config.getSubstitutor().replace((String) value);
}
else
{
return value;
}
}
}
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