PropertyContainer (Google App Engine API for Java)

com.google.appengine.api.datastore

Class PropertyContainer

  • java.lang.Object
    • com.google.appengine.api.datastore.PropertyContainer
  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable
    Direct Known Subclasses:
    EmbeddedEntity, Entity

    public abstract class PropertyContainer
extends java.lang.Object
implements java.io.Serializable, java.lang.Cloneable
    A mutable property container.
    See Also:
    Serialized Form

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method and Description
      java.util.Map<java.lang.String,java.lang.Object> getProperties()
      Gets all of the properties belonging to this container.
      java.lang.Object getProperty(java.lang.String propertyName)
      Gets the property with the specified name.
      boolean hasProperty(java.lang.String propertyName)
      Returns true if a property has been set.
      boolean isUnindexedProperty(java.lang.String propertyName)
      Returns true if propertyName has a value that will not be indexed.
      void removeProperty(java.lang.String propertyName)
      Removes any property with the specified name.
      void setIndexedProperty(java.lang.String propertyName, java.lang.Object value)
      Like {link #setProperty}, but requires that the value is indexable or a collection of indexable values.
      void setPropertiesFrom(PropertyContainer src)
      A convenience method that populates properties from those in the given container.
      void setProperty(java.lang.String propertyName, java.lang.Object value)
      Sets the property named, propertyName, to value.
      void setUnindexedProperty(java.lang.String propertyName, java.lang.Object value)
      Like #setProperty, but doesn't index the property in the built-in single property indexes or the user-defined composite indexes.

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • getProperty

        public java.lang.Object getProperty(java.lang.String propertyName)
        Gets the property with the specified name. The value returned may not be the same type as originally set via setProperty(java.lang.String, java.lang.Object).
        Returns:
        the property corresponding to propertyName.

      • getProperties

        public java.util.Map<java.lang.String,java.lang.Object> getProperties()
        Gets all of the properties belonging to this container.
        Returns:
        an unmodifiable Map of properties.

      • hasProperty

        public boolean hasProperty(java.lang.String propertyName)
        Returns true if a property has been set. If a property has been explicitly set to null, this function will return true.
        Returns:
        true iff the property named propertyName exists.

      • removeProperty

        public void removeProperty(java.lang.String propertyName)
        Removes any property with the specified name. If there is no property with this name set, simply does nothing.
        Throws:
        java.lang.NullPointerException - If propertyName is null.

      • setProperty

        public void setProperty(java.lang.String propertyName,
                        java.lang.Object value)
        Sets the property named, propertyName, to value.

        As the value is stored in the datastore, it is converted to the datastore's native type. This may include widening, such as converting a Short to a Long.

        If value is a Collection, the values will be stored in the datastore with the collection's iteration order with one caveat: all indexed values will come before all unindexed values (this can occur if the Collection contains both values that are normally indexed like strings, and values that are never indexed like Blob, Text and EmbeddedEntity).

        Overrides any existing value for this property, whether indexed or unindexed.

        Note that Blob, Text and EmbeddedEntity property values are never indexed. To store other types without being indexed, use setUnindexedProperty(java.lang.String, java.lang.Object).

        Parameters:
        value - may be one of the supported datatypes or a heterogeneous Collection of one of the supported datatypes.
        Throws:
        java.lang.IllegalArgumentException - If the value is not of a type that the data store supports.
        See Also:
        setUnindexedProperty(java.lang.String, java.lang.Object)

      • setIndexedProperty

        public void setIndexedProperty(java.lang.String propertyName,
                               java.lang.Object value)
        Like {link #setProperty}, but requires that the value is indexable or a collection of indexable values.

      • setUnindexedProperty

        public void setUnindexedProperty(java.lang.String propertyName,
                                 java.lang.Object value)
        Like #setProperty, but doesn't index the property in the built-in single property indexes or the user-defined composite indexes.
        Parameters:
        value - may be one of the supported datatypes, or a heterogeneous Collection of one of the supported datatypes.

        Overrides any existing value for this property, whether indexed or unindexed.

        Throws:
        java.lang.IllegalArgumentException - If the value is not of a type that the data store supports.
        See Also:
        setProperty(java.lang.String, java.lang.Object)

      • isUnindexedProperty

        public boolean isUnindexedProperty(java.lang.String propertyName)
        Returns true if propertyName has a value that will not be indexed. This includes Text, Blob, and any property added using setUnindexedProperty(java.lang.String, java.lang.Object).

        Note: The behavior of this method is not well defined in case of an indexed property whose value is a list that contains unindexable values.

      • setPropertiesFrom

        public void setPropertiesFrom(PropertyContainer src)
        A convenience method that populates properties from those in the given container.

        This method transfers information about unindexed properties and clones any mutable values.

        Parameters:
        src - The container from which we will populate ourself.