Package org.apache.commons.beanutils2

Class BeanMap

java.lang.Object
java.util.AbstractMap<String,Object>
org.apache.commons.beanutils2.BeanMap
All Implemented Interfaces:
Cloneable, Map<String,Object>
public class BeanMap extends AbstractMap<String,Object> implements Cloneable
An implementation of Map for JavaBeans which uses introspection to get and put properties in the bean.

If an exception occurs during attempts to get or set a property then the property is considered non existent in the Map

  • Field Details

    • NULL_ARGUMENTS

      public static final Object[] NULL_ARGUMENTS
      An empty array. Used to invoke accessors via reflection.

  • Constructor Details

    • BeanMap

      public BeanMap()
      Constructs a new empty BeanMap.

    • BeanMap

      public BeanMap(Object bean)
      Constructs a new BeanMap that operates on the specified bean. If the given bean is null, then this map will be empty.
      Parameters:
      bean - the bean for this map to operate on

  • Method Details

    • clear

      public void clear()
      This method reinitializes the bean map to have default values for the bean's properties. This is accomplished by constructing a new instance of the bean which the map uses as its underlying data source. This behavior for clear() differs from the Map contract in that the mappings are not actually removed from the map (the mappings for a BeanMap are fixed).
      Specified by:
      clear in interface Map<String,Object>
      Overrides:
      clear in class AbstractMap<String,Object>

    • clone

      public Object clone() throws CloneNotSupportedException
      Clone this bean map using the following process:
      • If there is no underlying bean, return a cloned BeanMap without a bean.
      • Since there is an underlying bean, try to instantiate a new bean of the same type using Class.newInstance().
      • If the instantiation fails, throw a CloneNotSupportedException
      • Clone the bean map and set the newly instantiated bean as the underlying bean for the bean map.
      • Copy each property that is both readable and writable from the existing object to a cloned bean map.
      • If anything fails along the way, throw a CloneNotSupportedException.
      Overrides:
      clone in class AbstractMap<String,Object>
      Returns:
      a cloned instance of this bean map
      Throws:
      CloneNotSupportedException - if the underlying bean cannot be cloned

    • containsKey

      public boolean containsKey(Object name)
      Returns true if the bean defines a property with the given name.

      The given name must be a String; if not, this method returns false. This method will also return false if the bean does not define a property with that name.

      Write-only properties will not be matched as the test operates against property read methods.

      Specified by:
      containsKey in interface Map<String,Object>
      Overrides:
      containsKey in class AbstractMap<String,Object>
      Parameters:
      name - the name of the property to check
      Returns:
      false if the given name is null or is not a String; false if the bean does not define a property with that name; or true if the bean does define a property with that name

    • convertType

      protected <R> Object convertType(Class<R> newType, Object value) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException
      Converts the given value to the given type. First, reflection is used to find a public constructor declared by the given class that takes one argument, which must be the precise type of the given value. If such a constructor is found, a new object is created by passing the given value to that constructor, and the newly constructed object is returned.

      If no such constructor exists, and the given type is a primitive type, then the given value is converted to a string using its toString() method, and that string is parsed into the correct primitive type using, for instance, Integer.valueOf(String) to convert the string into an int.

      If no special constructor exists and the given type is not a primitive type, this method returns the original value.

      Type Parameters:
      R - The return type.
      Parameters:
      newType - the type to convert the value to
      value - the value to convert
      Returns:
      the converted value
      Throws:
      NumberFormatException - if newType is a primitive type, and the string representation of the given value cannot be converted to that type
      InstantiationException - if the constructor found with reflection raises it
      InvocationTargetException - if the constructor found with reflection raises it
      IllegalAccessException - never
      IllegalArgumentException - never

    • createWriteMethodArguments

      protected Object[] createWriteMethodArguments(Method method, Object value) throws IllegalAccessException, ClassCastException
      Creates an array of parameters to pass to the given mutator method. If the given object is not the right type to pass to the method directly, it will be converted using convertType(Class,Object).
      Parameters:
      method - the mutator method
      value - the value to pass to the mutator method
      Returns:
      an array containing one object that is either the given value or a transformed value
      Throws:
      IllegalAccessException - if convertType(Class,Object) raises it
      IllegalArgumentException - if any other exception is raised by convertType(Class,Object)
      ClassCastException - if an error occurs creating the method args

    • entryIterator

      public Iterator<Map.Entry<String,Object>> entryIterator()
      Convenience method for getting an iterator over the entries.
      Returns:
      an iterator over the entries

    • entrySet

      public Set<Map.Entry<String,Object>> entrySet()
      Gets a Set of MapEntry objects that are the mappings for this BeanMap.

      Each MapEntry can be set but not removed.

      Specified by:
      entrySet in interface Map<String,Object>
      Specified by:
      entrySet in class AbstractMap<String,Object>
      Returns:
      the unmodifiable set of mappings

    • firePropertyChange

      protected void firePropertyChange(Object key, Object oldValue, Object newValue)
      Called during a successful put(String,Object) operation. Default implementation does nothing. Override to be notified of property changes in the bean caused by this map.
      Parameters:
      key - the name of the property that changed
      oldValue - the old value for that property
      newValue - the new value for that property

    • get

      public Object get(Object name)
      Gets the value of the bean's property with the given name.

      The given name must be a String and must not be null; otherwise, this method returns null. If the bean defines a property with the given name, the value of that property is returned. Otherwise, null is returned.

      Write-only properties will not be matched as the test operates against property read methods.

      Specified by:
      get in interface Map<String,Object>
      Overrides:
      get in class AbstractMap<String,Object>
      Parameters:
      name - the name of the property whose value to return
      Returns:
      the value of the property with that name

    • getBean

      public Object getBean()
      Gets the bean currently being operated on. The return value may be null if this map is empty.
      Returns:
      the bean being operated on by this map

    • getReadMethod

      protected Method getReadMethod(Object name)
      Gets the accessor for the property with the given name.
      Parameters:
      name - the name of the property
      Returns:
      null if the name is null; null if the name is not a String; null if no such property exists; or the accessor method for that property

    • getReadMethod

      public Method getReadMethod(String name)
      Gets the accessor for the property with the given name.
      Parameters:
      name - the name of the property
      Returns:
      the accessor method for the property, or null

    • getType

      public Class<?> getType(String name)
      Gets the type of the property with the given name.
      Parameters:
      name - the name of the property
      Returns:
      the type of the property, or null if no such property exists

    • getTypeTransformer

      protected <R> Function<Object,R> getTypeTransformer(Class<R> type)
      Gets a transformer for the given primitive type.
      Type Parameters:
      R - The transformer result type.
      Parameters:
      type - the primitive type whose transformer to return
      Returns:
      a transformer that will convert strings into that type, or null if the given type is not a primitive type

    • getWriteMethod

      protected Method getWriteMethod(Object name)
      Gets the mutator for the property with the given name.
      Parameters:
      name - the name of the
      Returns:
      null if the name is null; null if the name is not a String; null if no such property exists; null if the property is read-only; or the mutator method for that property

    • getWriteMethod

      public Method getWriteMethod(String name)
      Gets the mutator for the property with the given name.
      Parameters:
      name - the name of the property
      Returns:
      the mutator method for the property, or null

    • keyIterator

      public Iterator<String> keyIterator()
      Convenience method for getting an iterator over the keys.

      Write-only properties will not be returned in the iterator.

      Returns:
      an iterator over the keys

    • keySet

      public Set<String> keySet()
      Gets the keys for this BeanMap.

      Write-only properties are not included in the returned set of property names, although it is possible to set their value and to get their type.

      Specified by:
      keySet in interface Map<String,Object>
      Overrides:
      keySet in class AbstractMap<String,Object>
      Returns:
      BeanMap keys. The Set returned by this method is not modifiable.

    • logInfo

      protected void logInfo(Exception ex)
      Logs the given exception to System.out. Used to display warnings while accessing/mutating the bean.
      Parameters:
      ex - the exception to log

    • logWarn

      protected void logWarn(Exception ex)
      Logs the given exception to System.err. Used to display errors while accessing/mutating the bean.
      Parameters:
      ex - the exception to log

    • put

      public Object put(String name, Object value) throws IllegalArgumentException, ClassCastException
      Sets the bean property with the given name to the given value.
      Specified by:
      put in interface Map<String,Object>
      Overrides:
      put in class AbstractMap<String,Object>
      Parameters:
      name - the name of the property to set
      value - the value to set that property to
      Returns:
      the previous value of that property
      Throws:
      IllegalArgumentException - if the given name is null; if the given name is not a String; if the bean doesn't define a property with that name; or if the bean property with that name is read-only
      ClassCastException - if an error occurs creating the method args

    • putAllWriteable

      public void putAllWriteable(BeanMap map)
      Puts all of the writable properties from the given BeanMap into this BeanMap. Read-only and Write-only properties will be ignored.
      Parameters:
      map - the BeanMap whose properties to put

    • reinitialise

      protected void reinitialise()
      Reinitializes this bean. Called during setBean(Object). Does introspection to find properties.

    • setBean

      public void setBean(Object newBean)
      Sets the bean to be operated on by this map. The given value may be null, in which case this map will be empty.
      Parameters:
      newBean - the new bean to operate on

    • size

      public int size()
      Returns the number of properties defined by the bean.
      Specified by:
      size in interface Map<String,Object>
      Overrides:
      size in class AbstractMap<String,Object>
      Returns:
      the number of properties defined by the bean

    • toString

      public String toString()
      Renders a string representation of this object.
      Overrides:
      toString in class AbstractMap<String,Object>
      Returns:
      a String representation of this object

    • valueIterator

      public Iterator<Object> valueIterator()
      Convenience method for getting an iterator over the values.
      Returns:
      an iterator over the values

    • values

      public Collection<Object> values()
      Gets the values for the BeanMap.
      Specified by:
      values in interface Map<String,Object>
      Overrides:
      values in class AbstractMap<String,Object>
      Returns:
      values for the BeanMap. The returned collection is not modifiable.