Package org.apache.commons.beanutils

Class LazyDynaBean

  • All Implemented Interfaces:
    java.io.Serializable, DynaBean
    Direct Known Subclasses:
    LazyDynaMap
    public class LazyDynaBean
extends java.lang.Object
implements DynaBean, java.io.Serializable

    DynaBean which automatically adds properties to the DynaClass and provides Lazy List and Lazy Map features.

    DynaBeans deal with three types of properties - simple, indexed and mapped and have the following get() and set() methods for each of these types:

    • Simple property methods - get(name) and set(name, value)
    • Indexed property methods - get(name, index) and set(name, index, value)
    • Mapped property methods - get(name, key) and set(name, key, value)

    Getting Property Values

    Calling any of the get() methods, for a property which doesn't exist, returns null in this implementation.

    Setting Simple Properties

    The LazyDynaBean will automatically add a property to the DynaClass if it doesn't exist when the set(name, value) method is called.

         DynaBean myBean = new LazyDynaBean();
     myBean.set("myProperty", "myValue");

    Setting Indexed Properties

    If the property doesn't exist, the LazyDynaBean will automatically add a property with an ArrayList type to the DynaClass when the set(name, index, value) method is called. It will also instantiate a new ArrayList and automatically grow the List so that it is big enough to accommodate the index being set. ArrayList is the default indexed property that LazyDynaBean uses but this can be easily changed by overriding the defaultIndexedProperty(name) method.

         DynaBean myBean = new LazyDynaBean()
     myBean.set("myIndexedProperty", 0, "myValue1");
     myBean.set("myIndexedProperty", 1, "myValue2");

    If the indexed property does exist in the DynaClass but is set to null in the LazyDynaBean, then it will instantiate a new List or Array as specified by the property's type in the DynaClass and automatically grow the List or Array so that it is big enough to accommodate the index being set.

    DynaBean myBean = new LazyDynaBean();
     MutableDynaClass myClass = (MutableDynaClass)myBean.getDynaClass();
     myClass.add("myIndexedProperty", int[].class);
     myBean.set("myIndexedProperty", 0, Integer.valueOf(10));
     myBean.set("myIndexedProperty", 1, Integer.valueOf(20));

    Setting Mapped Properties

    If the property doesn't exist, the LazyDynaBean will automatically add a property with a HashMap type to the DynaClass and instantiate a new HashMap in the DynaBean when the set(name, key, value) method is called. HashMap is the default mapped property that LazyDynaBean uses but this can be easily changed by overriding the defaultMappedProperty(name) method.

         DynaBean myBean = new LazyDynaBean();
     myBean.set("myMappedProperty", "myKey", "myValue");

    If the mapped property does exist in the DynaClass but is set to null in the LazyDynaBean, then it will instantiate a new Map as specified by the property's type in the DynaClass.

         DynaBean myBean = new LazyDynaBean();
     MutableDynaClass myClass = (MutableDynaClass)myBean.getDynaClass();
     myClass.add("myMappedProperty", TreeMap.class);
     myBean.set("myMappedProperty", "myKey", "myValue");

    Restricted DynaClass

    MutableDynaClass have a facility to restrict the DynaClass so that its properties cannot be modified. If the MutableDynaClass is restricted then calling any of the set() methods for a property which doesn't exist will result in a IllegalArgumentException being thrown.

    See Also:
    LazyDynaClass, Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected static java.math.BigDecimal BigDecimal_ZERO
      BigDecimal Zero
      protected static java.math.BigInteger BigInteger_ZERO
      BigInteger Zero
      protected static java.lang.Byte Byte_ZERO
      Byte Zero
      protected static java.lang.Character Character_SPACE
      Character Space
      protected static java.lang.Double Double_ZERO
      Double Zero
      protected MutableDynaClass dynaClass
      The MutableDynaClass "base class" that this DynaBean is associated with.
      protected static java.lang.Float Float_ZERO
      Float Zero
      protected static java.lang.Integer Integer_ZERO
      Integer Zero
      private org.apache.commons.logging.Log logger
      Commons Logging
      protected static java.lang.Long Long_ZERO
      Long Zero
      private java.util.Map<java.lang.String,​java.lang.Object> mapDecorator
      Map decorator for this DynaBean
      private static long serialVersionUID  
      protected static java.lang.Short Short_ZERO
      Short Zero
      protected java.util.Map<java.lang.String,​java.lang.Object> values
      The MutableDynaClass "base class" that this DynaBean is associated with.

    • Constructor Summary

      Constructors 
      Constructor Description
      LazyDynaBean()
      Construct a new LazyDynaBean with a LazyDynaClass instance.
      LazyDynaBean​(java.lang.String name)
      Construct a new LazyDynaBean with a LazyDynaClass instance.
      LazyDynaBean​(DynaClass dynaClass)
      Construct a new DynaBean associated with the specified DynaClass instance - if its not a MutableDynaClass then a new LazyDynaClass is created and the properties copied.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean contains​(java.lang.String name, java.lang.String key)
      Does the specified mapped property contain a value for the specified key value?
      protected java.lang.Object createDynaBeanProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of a 'DynaBean' Property.
      protected java.lang.Object createIndexedProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of an 'Indexed' Property
      protected java.lang.Object createMappedProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of a 'Mapped' Property
      protected java.lang.Object createNumberProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of a java.lang.Number Property.
      protected java.lang.Object createOtherProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of other Property types
      protected java.lang.Object createPrimitiveProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of a 'Primitive' Property.
      protected java.lang.Object createProperty​(java.lang.String name, java.lang.Class<?> type)
      Create a new Instance of a Property
      protected java.lang.Object defaultIndexedProperty​(java.lang.String name)
      Creates a new ArrayList for an 'indexed' property which doesn't exist.
      protected java.util.Map<java.lang.String,​java.lang.Object> defaultMappedProperty​(java.lang.String name)
      Creates a new HashMap for a 'mapped' property which doesn't exist.
      java.lang.Object get​(java.lang.String name)
      Return the value of a simple property with the specified name.
      java.lang.Object get​(java.lang.String name, int index)
      Return the value of an indexed property with the specified name.
      java.lang.Object get​(java.lang.String name, java.lang.String key)
      Return the value of a mapped property with the specified name.
      DynaClass getDynaClass()
      Return the DynaClass instance that describes the set of properties available for this DynaBean.
      java.util.Map<java.lang.String,​java.lang.Object> getMap()
      Return a Map representation of this DynaBean.
      protected java.lang.Object growIndexedProperty​(java.lang.String name, java.lang.Object indexedProperty, int index)
      Grow the size of an indexed property.
      protected boolean isAssignable​(java.lang.Class<?> dest, java.lang.Class<?> source)
      Is an object of the source class assignable to the destination class?
      protected boolean isDynaProperty​(java.lang.String name)
      Indicates if there is a property with the specified name.
      private org.apache.commons.logging.Log logger()
      Returns the Log.
      protected java.util.Map<java.lang.String,​java.lang.Object> newMap()
      Creates a new instance of the Map.
      void remove​(java.lang.String name, java.lang.String key)
      Remove any existing value for the specified key on the specified mapped property.
      void set​(java.lang.String name, int index, java.lang.Object value)
      Set the value of an indexed property with the specified name.
      void set​(java.lang.String name, java.lang.Object value)
      Set the value of a simple property with the specified name.
      void set​(java.lang.String name, java.lang.String key, java.lang.Object value)
      Set the value of a mapped property with the specified name.
      int size​(java.lang.String name)
      Return the size of an indexed or mapped property.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • BigInteger_ZERO

        protected static final java.math.BigInteger BigInteger_ZERO
        BigInteger Zero

      • BigDecimal_ZERO

        protected static final java.math.BigDecimal BigDecimal_ZERO
        BigDecimal Zero

      • Character_SPACE

        protected static final java.lang.Character Character_SPACE
        Character Space

      • Byte_ZERO

        protected static final java.lang.Byte Byte_ZERO
        Byte Zero

      • Short_ZERO

        protected static final java.lang.Short Short_ZERO
        Short Zero

      • Integer_ZERO

        protected static final java.lang.Integer Integer_ZERO
        Integer Zero

      • Long_ZERO

        protected static final java.lang.Long Long_ZERO
        Long Zero

      • Float_ZERO

        protected static final java.lang.Float Float_ZERO
        Float Zero

      • Double_ZERO

        protected static final java.lang.Double Double_ZERO
        Double Zero

      • logger

        private transient org.apache.commons.logging.Log logger
        Commons Logging

      • values

        protected java.util.Map<java.lang.String,​java.lang.Object> values
        The MutableDynaClass "base class" that this DynaBean is associated with.

      • mapDecorator

        private transient java.util.Map<java.lang.String,​java.lang.Object> mapDecorator
        Map decorator for this DynaBean

      • dynaClass

        protected MutableDynaClass dynaClass
        The MutableDynaClass "base class" that this DynaBean is associated with.

    • Constructor Detail

      • LazyDynaBean

        public LazyDynaBean()
        Construct a new LazyDynaBean with a LazyDynaClass instance.

      • LazyDynaBean

        public LazyDynaBean​(DynaClass dynaClass)
        Construct a new DynaBean associated with the specified DynaClass instance - if its not a MutableDynaClass then a new LazyDynaClass is created and the properties copied.
        Parameters:
        dynaClass - The DynaClass we are associated with

      • LazyDynaBean

        public LazyDynaBean​(java.lang.String name)
        Construct a new LazyDynaBean with a LazyDynaClass instance.
        Parameters:
        name - Name of this DynaBean class

    • Method Detail

      • contains

        public boolean contains​(java.lang.String name,
                        java.lang.String key)
        Does the specified mapped property contain a value for the specified key value?
        Specified by:
        contains in interface DynaBean
        Parameters:
        name - Name of the property to check
        key - Name of the key to check
        Returns:
        true if the mapped property contains a value for the specified key, otherwise false
        Throws:
        java.lang.IllegalArgumentException - if no property name is specified

      • createDynaBeanProperty

        protected java.lang.Object createDynaBeanProperty​(java.lang.String name,
                                                  java.lang.Class<?> type)
        Create a new Instance of a 'DynaBean' Property.
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createIndexedProperty

        protected java.lang.Object createIndexedProperty​(java.lang.String name,
                                                 java.lang.Class<?> type)
        Create a new Instance of an 'Indexed' Property
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createMappedProperty

        protected java.lang.Object createMappedProperty​(java.lang.String name,
                                                java.lang.Class<?> type)
        Create a new Instance of a 'Mapped' Property
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createNumberProperty

        protected java.lang.Object createNumberProperty​(java.lang.String name,
                                                java.lang.Class<?> type)
        Create a new Instance of a java.lang.Number Property.
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createOtherProperty

        protected java.lang.Object createOtherProperty​(java.lang.String name,
                                               java.lang.Class<?> type)
        Create a new Instance of other Property types
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createPrimitiveProperty

        protected java.lang.Object createPrimitiveProperty​(java.lang.String name,
                                                   java.lang.Class<?> type)
        Create a new Instance of a 'Primitive' Property.
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • createProperty

        protected java.lang.Object createProperty​(java.lang.String name,
                                          java.lang.Class<?> type)
        Create a new Instance of a Property
        Parameters:
        name - The name of the property
        type - The class of the property
        Returns:
        The new value

      • defaultIndexedProperty

        protected java.lang.Object defaultIndexedProperty​(java.lang.String name)

        Creates a new ArrayList for an 'indexed' property which doesn't exist.

        This method should be overridden if an alternative List or Array implementation is required for 'indexed' properties.

        Parameters:
        name - Name of the 'indexed property.
        Returns:
        The default value for an indexed property (java.util.ArrayList)

      • defaultMappedProperty

        protected java.util.Map<java.lang.String,​java.lang.Object> defaultMappedProperty​(java.lang.String name)

        Creates a new HashMap for a 'mapped' property which doesn't exist.

        This method can be overridden if an alternative Map implementation is required for 'mapped' properties.

        Parameters:
        name - Name of the 'mapped property.
        Returns:
        The default value for a mapped property (java.util.HashMap)

      • get

        public java.lang.Object get​(java.lang.String name)

        Return the value of a simple property with the specified name.

        N.B. Returns null if there is no property of the specified name.

        Specified by:
        get in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be retrieved.
        Returns:
        The property's value
        Throws:
        java.lang.IllegalArgumentException - if no property name is specified

      • get

        public java.lang.Object get​(java.lang.String name,
                            int index)

        Return the value of an indexed property with the specified name.

        N.B. Returns null if there is no 'indexed' property of the specified name.

        Specified by:
        get in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be retrieved
        index - Index of the value to be retrieved
        Returns:
        The indexed property's value
        Throws:
        java.lang.IllegalArgumentException - if the specified property exists, but is not indexed
        java.lang.IndexOutOfBoundsException - if the specified index is outside the range of the underlying property

      • get

        public java.lang.Object get​(java.lang.String name,
                            java.lang.String key)

        Return the value of a mapped property with the specified name.

        N.B. Returns null if there is no 'mapped' property of the specified name.

        Specified by:
        get in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be retrieved
        key - Key of the value to be retrieved
        Returns:
        The mapped property's value
        Throws:
        java.lang.IllegalArgumentException - if the specified property exists, but is not mapped

      • getDynaClass

        public DynaClass getDynaClass()
        Return the DynaClass instance that describes the set of properties available for this DynaBean.
        Specified by:
        getDynaClass in interface DynaBean
        Returns:
        The associated DynaClass

      • getMap

        public java.util.Map<java.lang.String,​java.lang.Object> getMap()
        Return a Map representation of this DynaBean.

        This, for example, could be used in JSTL in the following way to access a DynaBean's fooProperty:

        • ${myDynaBean.map.fooProperty}
        Returns:
        a Map representation of this DynaBean

      • growIndexedProperty

        protected java.lang.Object growIndexedProperty​(java.lang.String name,
                                               java.lang.Object indexedProperty,
                                               int index)
        Grow the size of an indexed property.
        Parameters:
        name - The name of the property
        indexedProperty - The current property value
        index - The indexed value to grow the property to (i.e. one less than the required size)
        Returns:
        The new property value (grown to the appropriate size)

      • isAssignable

        protected boolean isAssignable​(java.lang.Class<?> dest,
                               java.lang.Class<?> source)
        Is an object of the source class assignable to the destination class?
        Parameters:
        dest - Destination class
        source - Source class
        Returns:
        true if the source class is assignable to the destination class, otherwise false

      • isDynaProperty

        protected boolean isDynaProperty​(java.lang.String name)
        Indicates if there is a property with the specified name.
        Parameters:
        name - The name of the property to check
        Returns:
        true if there is a property of the specified name, otherwise false

      • logger

        private org.apache.commons.logging.Log logger()

        Returns the Log.

      • newMap

        protected java.util.Map<java.lang.String,​java.lang.Object> newMap()

        Creates a new instance of the Map.

        Returns:
        a new Map instance

      • remove

        public void remove​(java.lang.String name,
                   java.lang.String key)
        Remove any existing value for the specified key on the specified mapped property.
        Specified by:
        remove in interface DynaBean
        Parameters:
        name - Name of the property for which a value is to be removed
        key - Key of the value to be removed
        Throws:
        java.lang.IllegalArgumentException - if there is no property of the specified name

      • set

        public void set​(java.lang.String name,
                int index,
                java.lang.Object value)
        Set the value of an indexed property with the specified name.
        Specified by:
        set in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be set
        index - Index of the property to be set
        value - Value to which this property is to be set
        Throws:
        ConversionException - if the specified value cannot be converted to the type required for this property
        java.lang.IllegalArgumentException - if there is no property of the specified name
        java.lang.IllegalArgumentException - if the specified property exists, but is not indexed
        java.lang.IndexOutOfBoundsException - if the specified index is outside the range of the underlying property

      • set

        public void set​(java.lang.String name,
                java.lang.Object value)
        Set the value of a simple property with the specified name.
        Specified by:
        set in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be set
        value - Value to which this property is to be set
        Throws:
        java.lang.IllegalArgumentException - if this is not an existing property name for our DynaClass and the MutableDynaClass is restricted
        ConversionException - if the specified value cannot be converted to the type required for this property
        java.lang.NullPointerException - if an attempt is made to set a primitive property to null

      • set

        public void set​(java.lang.String name,
                java.lang.String key,
                java.lang.Object value)
        Set the value of a mapped property with the specified name.
        Specified by:
        set in interface DynaBean
        Parameters:
        name - Name of the property whose value is to be set
        key - Key of the property to be set
        value - Value to which this property is to be set
        Throws:
        ConversionException - if the specified value cannot be converted to the type required for this property
        java.lang.IllegalArgumentException - if there is no property of the specified name
        java.lang.IllegalArgumentException - if the specified property exists, but is not mapped

      • size

        public int size​(java.lang.String name)

        Return the size of an indexed or mapped property.

        Parameters:
        name - Name of the property
        Returns:
        The indexed or mapped property size
        Throws:
        java.lang.IllegalArgumentException - if no property name is specified