////////////////////////////////////////////////////////////////////////////////

 // checkstyle: Checks Java source code for adherence to a set of rules.

 // Copyright (C) 2001-2014  Oliver Burn

 //

 // This library is free software; you can redistribute it and/or

 // modify it under the terms of the GNU Lesser General Public

 // License as published by the Free Software Foundation; either

 // version 2.1 of the License, or (at your option) any later version.

 //

 // This library is distributed in the hope that it will be useful,

 // but WITHOUT ANY WARRANTY; without even the implied warranty of

 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 // Lesser General Public License for more details.

 //

 // You should have received a copy of the GNU Lesser General Public

 // License along with this library; if not, write to the Free Software

 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 ////////////////////////////////////////////////////////////////////////////////

 package com.puppycrawl.tools.checkstyle.api;

 import com.google.common.collect.Lists;

 import java.beans.PropertyDescriptor;

 import java.lang.reflect.InvocationTargetException;

 import java.util.Collection;

 import java.util.List;

 import java.util.StringTokenizer;

 import org.apache.commons.beanutils.BeanUtilsBean;

 import org.apache.commons.beanutils.ConversionException;

 import org.apache.commons.beanutils.ConvertUtilsBean;

 import org.apache.commons.beanutils.Converter;

 import org.apache.commons.beanutils.PropertyUtils;

 import org.apache.commons.beanutils.PropertyUtilsBean;

 import org.apache.commons.beanutils.converters.ArrayConverter;

 import org.apache.commons.beanutils.converters.BooleanConverter;

 import org.apache.commons.beanutils.converters.ByteConverter;

 import org.apache.commons.beanutils.converters.CharacterConverter;

 import org.apache.commons.beanutils.converters.DoubleConverter;

 import org.apache.commons.beanutils.converters.FloatConverter;

 import org.apache.commons.beanutils.converters.IntegerConverter;

 import org.apache.commons.beanutils.converters.LongConverter;

 import org.apache.commons.beanutils.converters.ShortConverter;

 /**

  * A Java Bean that implements the component lifecycle interfaces by

  * calling the bean's setters for all configuration attributes.

  * @author lkuehne

  */

 public class AutomaticBean

     implements Configurable, Contextualizable

 {

     /** the configuration of this bean */

     private Configuration mConfiguration;

     /**

      * Creates a BeanUtilsBean that is configured to use

      * type converters that throw a ConversionException

      * instead of using the default value when something

      * goes wrong.

      *

      * @return a configured BeanUtilsBean

      */

     private static BeanUtilsBean createBeanUtilsBean()

     {

         final ConvertUtilsBean cub = new ConvertUtilsBean();

         // TODO: is there a smarter way to tell beanutils not to use defaults?

         cub.register(new BooleanConverter(), Boolean.TYPE);

         cub.register(new BooleanConverter(), Boolean.class);

         cub.register(new ArrayConverter(

             boolean[].class, new BooleanConverter()), boolean[].class);

         cub.register(new ByteConverter(), Byte.TYPE);

         cub.register(new ByteConverter(), Byte.class);

         cub.register(new ArrayConverter(byte[].class, new ByteConverter()),

             byte[].class);

         cub.register(new CharacterConverter(), Character.TYPE);

         cub.register(new CharacterConverter(), Character.class);

         cub.register(new ArrayConverter(char[].class, new CharacterConverter()),

             char[].class);

         cub.register(new DoubleConverter(), Double.TYPE);

         cub.register(new DoubleConverter(), Double.class);

         cub.register(new ArrayConverter(double[].class, new DoubleConverter()),

             double[].class);

         cub.register(new FloatConverter(), Float.TYPE);

         cub.register(new FloatConverter(), Float.class);

         cub.register(new ArrayConverter(float[].class, new FloatConverter()),

             float[].class);

         cub.register(new IntegerConverter(), Integer.TYPE);

         cub.register(new IntegerConverter(), Integer.class);

         cub.register(new ArrayConverter(int[].class, new IntegerConverter()),

             int[].class);

         cub.register(new LongConverter(), Long.TYPE);

         cub.register(new LongConverter(), Long.class);

         cub.register(new ArrayConverter(long[].class, new LongConverter()),

             long[].class);

         cub.register(new ShortConverter(), Short.TYPE);

         cub.register(new ShortConverter(), Short.class);

         cub.register(new ArrayConverter(short[].class, new ShortConverter()),

             short[].class);

         cub.register(new RelaxedStringArrayConverter(), String[].class);

         // BigDecimal, BigInteger, Class, Date, String, Time, TimeStamp

         // do not use defaults in the default configuration of ConvertUtilsBean

         return new BeanUtilsBean(cub, new PropertyUtilsBean());

     }

     /**

      * Implements the Configurable interface using bean introspection.

      *

      * Subclasses are allowed to add behaviour. After the bean

      * based setup has completed first the method

      * {@link #finishLocalSetup finishLocalSetup}

      * is called to allow completion of the bean's local setup,

      * after that the method {@link #setupChild setupChild}

      * is called for each {@link Configuration#getChildren child Configuration}

      * of <code>aConfiguration</code>.

      *

      * @param aConfiguration {@inheritDoc}

      * @throws CheckstyleException {@inheritDoc}

      * @see Configurable

      */

     public final void configure(Configuration aConfiguration)

         throws CheckstyleException

     {

         mConfiguration = aConfiguration;

         final BeanUtilsBean beanUtils = createBeanUtilsBean();

         // TODO: debug log messages

         final String[] attributes = aConfiguration.getAttributeNames();

         for (final String key : attributes) {

             final String value = aConfiguration.getAttribute(key);

             try {

                 // BeanUtilsBean.copyProperties silently ignores missing setters

                 // for key, so we have to go through great lengths here to

                 // figure out if the bean property really exists.

                 final PropertyDescriptor pd =

                     PropertyUtils.getPropertyDescriptor(this, key);

                 if ((pd == null) || (pd.getWriteMethod() == null)) {

                     throw new CheckstyleException(

                         "Property '" + key + "' in module "

                         + aConfiguration.getName()

                         + " does not exist, please check the documentation");

                 }

                 // finally we can set the bean property

                 beanUtils.copyProperty(this, key, value);

             }

             catch (final InvocationTargetException e) {

                 throw new CheckstyleException(

                     "Cannot set property '" + key + "' in module "

                     + aConfiguration.getName() + " to '" + value

                     + "': " + e.getTargetException().getMessage(), e);

             }

             catch (final IllegalAccessException e) {

                 throw new CheckstyleException(

                     "cannot access " + key + " in "

                     + this.getClass().getName(), e);

             }

             catch (final NoSuchMethodException e) {

                 throw new CheckstyleException(

                     "cannot access " + key + " in "

                     + this.getClass().getName(), e);

             }

             catch (final IllegalArgumentException e) {

                 throw new CheckstyleException(

                     "illegal value '" + value + "' for property '" + key

                     + "' of module " + aConfiguration.getName(), e);

             }

             catch (final ConversionException e) {

                 throw new CheckstyleException(

                     "illegal value '" + value + "' for property '" + key

                     + "' of module " + aConfiguration.getName(), e);

             }

         }

         finishLocalSetup();

         final Configuration[] childConfigs = aConfiguration.getChildren();

         for (final Configuration childConfig : childConfigs) {

             setupChild(childConfig);

         }

     }

     /**

      * Implements the Contextualizable interface using bean introspection.

      * @param aContext {@inheritDoc}

      * @throws CheckstyleException {@inheritDoc}

      * @see Contextualizable

      */

     public final void contextualize(Context aContext)

         throws CheckstyleException

     {

         final BeanUtilsBean beanUtils = createBeanUtilsBean();

         // TODO: debug log messages

         final Collection<String> attributes = aContext.getAttributeNames();

         for (final String key : attributes) {

             final Object value = aContext.get(key);

             try {

                 beanUtils.copyProperty(this, key, value);

             }

             catch (final InvocationTargetException e) {

                 // TODO: log.debug("The bean " + this.getClass()

                 // + " is not interested in " + value)

                 throw new CheckstyleException("cannot set property "

                     + key + " to value " + value + " in bean "

                     + this.getClass().getName(), e);

             }

             catch (final IllegalAccessException e) {

                 throw new CheckstyleException(

                     "cannot access " + key + " in "

                     + this.getClass().getName(), e);

             }

             catch (final IllegalArgumentException e) {

                 throw new CheckstyleException(

                     "illegal value '" + value + "' for property '" + key

                     + "' of bean " + this.getClass().getName(), e);

             }

             catch (final ConversionException e) {

                 throw new CheckstyleException(

                     "illegal value '" + value + "' for property '" + key

                     + "' of bean " + this.getClass().getName(), e);

             }

         }

     }

     /**

      * Returns the configuration that was used to configure this component.

      * @return the configuration that was used to configure this component.

      */

     protected final Configuration getConfiguration()

     {

         return mConfiguration;

     }

     /**

      * Provides a hook to finish the part of this component's setup that

      * was not handled by the bean introspection.

      * <p>

      * The default implementation does nothing.

      * </p>

      * @throws CheckstyleException if there is a configuration error.

      */

     protected void finishLocalSetup() throws CheckstyleException

     {

     }

     /**

      * Called by configure() for every child of this component's Configuration.

      * <p>

      * The default implementation does nothing.

      * </p>

      * @param aChildConf a child of this component's Configuration

      * @throws CheckstyleException if there is a configuration error.

      * @see Configuration#getChildren

      */

     protected void setupChild(Configuration aChildConf)

         throws CheckstyleException

     {

     }

     /**

      * A converter that does not care whether the array elements contain String

      * characters like '*' or '_'. The normal ArrayConverter class has problems

      * with this characters.

      */

     private static class RelaxedStringArrayConverter implements Converter

     {

         /** {@inheritDoc} */

         public Object convert(@SuppressWarnings("rawtypes") Class aType,

             Object aValue)

         {

             if (null == aType) {

                 throw new ConversionException("Cannot convert from null.");

             }

             // Convert to a String and trim it for the tokenizer.

             final StringTokenizer st = new StringTokenizer(

                 aValue.toString().trim(), ",");

             final List<String> result = Lists.newArrayList();

             while (st.hasMoreTokens()) {

                 final String token = st.nextToken();

                 result.add(token.trim());

             }

             return result.toArray(new String[result.size()]);

         }

     }

 }