Subversion Repositories bacoAlunos

package com.owlike.genson.reflect;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collections;

import java.util.Comparator;

import java.util.LinkedHashMap;

import java.util.List;

import java.util.Map;

import com.owlike.genson.*;

import com.owlike.genson.reflect.BeanCreator.BeanCreatorProperty;

import com.owlike.genson.stream.ObjectReader;

import com.owlike.genson.stream.ObjectWriter;

/**

 * BeanDescriptors are used to serialize/deserialize objects based on their fields, methods and

 * constructors. By default it is supposed to work on JavaBeans, however it can be configured and

 * extended to support different kind of objects.

 * <p/>

 * In most cases BeanDescriptors should not be used directly as it is used internally to support

 * objects not handled by the default Converters. The most frequent case when you will use directly

 * a BeanDescriptor is when you want to deserialize into an existing instance. Here is an example :

 * <p/>

 * <pre>

 * Genson genson = new Genson();

 * BeanDescriptorProvider provider = genson.getBeanDescriptorProvider();

 * BeanDescriptor<MyClass> descriptor = provider.provide(MyClass.class, genson);

 *

 * MyClass existingInstance = descriptor.deserialize(existingInstance, new JsonReader("{}"),

 *              new Context(genson));

 * </pre>

 *

 * @param <T> type that this BeanDescriptor can serialize and deserialize.

 * @author eugen

 * @see BeanDescriptorProvider

 */

public class BeanDescriptor<T> implements Converter<T> {

  final Class<?> fromDeclaringClass;

  final Class<T> ofClass;

  final Map<String, PropertyMutator> mutableProperties;

  final List<PropertyAccessor> accessibleProperties;

  final boolean failOnMissingProperty;

  final BeanCreator creator;

  private final boolean _noArgCtr;

  private static final 5+0%2Fdocs%2Fapi+Object">Object MISSING = new 5+0%2Fdocs%2Fapi+Object">Object();

  // Used as a cache so we just copy it instead of recreating and assigning the default values

  private 5+0%2Fdocs%2Fapi+Object">Object[] globalCreatorArgs;

  private final static Comparator<BeanProperty> _readablePropsComparator = new Comparator<BeanProperty>() {

    public int compare(BeanProperty o1, BeanProperty o2) {

      return o1.name.compareToIgnoreCase(o2.name);

    }

  };

  public 1.5.0/docs/api/java/beans/BeanDescriptor.html">BeanDescriptor(Class<T> forClass, Class<?> fromDeclaringClass,

                        List<PropertyAccessor> readableBps,

                        Map<String, PropertyMutator> writableBps, BeanCreator creator,

                        boolean failOnMissingProperty) {

    this.ofClass = forClass;

    this.fromDeclaringClass = fromDeclaringClass;

    this.creator = creator;

    this.failOnMissingProperty = failOnMissingProperty;

    mutableProperties = writableBps;

    1.5.0/docs/api/java/util/Collections.html">Collections.sort(readableBps, _readablePropsComparator);

    accessibleProperties = 1.5.0/docs/api/java/util/Collections.html">Collections.unmodifiableList(readableBps);

    if (this.creator != null) {

      _noArgCtr = this.creator.parameters.size() == 0;

      globalCreatorArgs = new 5+0%2Fdocs%2Fapi+Object">Object[creator.parameters.size()];

      1.5.0/docs/api/java/util/Arrays.html">Arrays.fill(globalCreatorArgs, MISSING);

    } else {

      _noArgCtr = false;

    }

  }

  public boolean isReadable() {

    return !accessibleProperties.isEmpty();

  }

  public boolean isWritable() {

    return creator != null;

  }

  public void serialize(T obj, ObjectWriter writer, 5+0%2Fdocs%2Fapi+Context">Context ctx) {

    writer.beginObject();

    RuntimePropertyFilter runtimePropertyFilter = ctx.genson.runtimePropertyFilter();

    for (PropertyAccessor accessor : accessibleProperties) {

      if (runtimePropertyFilter.shouldInclude(accessor, ctx)) accessor.serialize(obj, writer, ctx);

    }

    writer.endObject();

  }

  public T deserialize(ObjectReader reader, 5+0%2Fdocs%2Fapi+Context">Context ctx) {

    T bean = null;

    // optimization for default ctr

    if (_noArgCtr) {

      bean = ofClass.cast(creator.create());

      deserialize(bean, reader, ctx);

    } else {

      if (creator == null)

        throw new JsonBindingException("No constructor has been found for type "

          + ofClass);

      bean = _deserWithCtrArgs(reader, ctx);

    }

    return bean;

  }

  public void deserialize(T into, ObjectReader reader, 5+0%2Fdocs%2Fapi+Context">Context ctx) {

    reader.beginObject();

    RuntimePropertyFilter runtimePropertyFilter = ctx.genson.runtimePropertyFilter();

    for (; reader.hasNext(); ) {

      reader.next();

      1.5.0/docs/api/java/lang/String.html">String propName = reader.name();

      PropertyMutator mutator = mutableProperties.get(propName);

      if (mutator != null) {

        if (runtimePropertyFilter.shouldInclude(mutator, ctx)) {

          mutator.deserialize(into, reader, ctx);

        } else {

          reader.skipValue();

        }

      } else if (failOnMissingProperty) throw missingPropertyException(propName);

      else reader.skipValue();

    }

    reader.endObject();

  }

  protected T _deserWithCtrArgs(ObjectReader reader, 5+0%2Fdocs%2Fapi+Context">Context ctx) {

    List<String> names = new ArrayList<String>();

    List<Object> values = new ArrayList<Object>();

    RuntimePropertyFilter runtimePropertyFilter = ctx.genson.runtimePropertyFilter();

    reader.beginObject();

    for (; reader.hasNext(); ) {

      reader.next();

      1.5.0/docs/api/java/lang/String.html">String propName = reader.name();

      PropertyMutator muta = mutableProperties.get(propName);

      if (muta != null) {

        if (runtimePropertyFilter.shouldInclude(muta, ctx)) {

          5+0%2Fdocs%2Fapi+Object">Object param = muta.deserialize(reader, ctx);

          names.add(propName);

          values.add(param);

        } else {

          reader.skipValue();

        }

      } else if (failOnMissingProperty) throw missingPropertyException(propName);

      else reader.skipValue();

    }

    int size = names.size();

    int foundCtrParameters = 0;

    5+0%2Fdocs%2Fapi+Object">Object[] creatorArgs = globalCreatorArgs.clone();

    1.5.0/docs/api/java/lang/String.html">String[] newNames = new 1.5.0/docs/api/java/lang/String.html">String[size];

    5+0%2Fdocs%2Fapi+Object">Object[] newValues = new 5+0%2Fdocs%2Fapi+Object">Object[size];

    for (int i = 0, j = 0; i < size; i++) {

      BeanCreatorProperty mp = creator.paramsAndAliases.get(names.get(i));

      if (mp != null) {

        creatorArgs[mp.index] = values.get(i);

        foundCtrParameters++;

      } else {

        newNames[j] = names.get(i);

        newValues[j] = values.get(i);

        j++;

      }

    }

    if (foundCtrParameters < creator.parameters.size()) updateWithDefaultValues(creatorArgs, ctx.genson);

    T bean = ofClass.cast(creator.create(creatorArgs));

    for (int i = 0; i < size; i++) {

      PropertyMutator property = mutableProperties.get(newNames[i]);

      if (property != null) property.mutate(bean, newValues[i]);

    }

    reader.endObject();

    return bean;

  }

  private void updateWithDefaultValues(5+0%2Fdocs%2Fapi+Object">Object[] creatorArgs, Genson genson) {

    for (int i = 0; i < creatorArgs.length; i++) {

      if (creatorArgs[i] == MISSING) {

        for (BeanCreatorProperty property : creator.parameters.values()) {

          if (property.index == i) {

            creatorArgs[i] = genson.defaultValue(property.getRawClass());

            break;

          }

        }

      }

    }

  }

  public Class<T> getOfClass() {

    return ofClass;

  }

  private JsonBindingException missingPropertyException(1.5.0/docs/api/java/lang/String.html">String name) {

   return new JsonBindingException("No matching property in " + getOfClass() + " for key " + name);

  }

}