javax.jcr
Interface Value

public interface Value

A generic holder for the value of a property. A Value object can be used without knowing the actual property type (STRING, DOUBLE, BINARY etc.).

Any implementation of this interface must adhere to the following behavior:

• A Value object can be read using type-specific get methods. These methods are divided into two groups:
  • The non-stream get methods getString(), getDate(), getLong(), getDouble() and getBoolean().
  • getStream().
• Once a Value object has been read once using getStream(), all subsequent calls to getStream() will return the same Stream object. This may mean, for example, that the stream returned is fully or partially consumed. In order to get a fresh stream the Value object must be reacquired via Property.getValue() or Property.getValues().
• Once a Value object has been read once using getStream(), any subsequent call to any of the non-stream get methods will throw an IllegalStateException. In order to successfully invoke a non-stream get method, the Value must be reacquired.
• Once a Value object has been read once using a non-stream get method, any subsequent call to getStream() will throw an IllegalStateException. In order to successfully invoke getStream(), the Value must be reacquired.

Two Value instances, v1 and v2, are considered equal if and only if:

• v1.getType() == v2.getType(), and,
• v1.getString().equals(v2.getString())

Actually comparing two Value instances by converting them to string form may not be practical in some cases (for example, if the values are very large binaries). Consequently, the above is intended as a normative definition of Value equality but not as a procedural test of equality. It is assumed that implementations will have efficient means of determining equality that conform with the above definition.

Method Summary

boolean	getBoolean() Returns a Boolean representation of this value.
java.util.Calendar	getDate() Returns a Calendar representation of this value.
double	getDouble() Returns a double representation of this value.
long	getLong() Returns a long representation of this value.
java.io.InputStream	getStream() Returns an InputStream representation of this value.
java.lang.String	getString() Returns a String representation of this value.
int	getType() Returns the type of this Value.

Method Detail

getString

public java.lang.String getString()
                           throws ValueFormatException,
                                  java.lang.IllegalStateException,
                                  RepositoryException

Returns a String representation of this value.

If this value cannot be converted to a string, a ValueFormatException is thrown.

If getStream has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getString.

A RepositoryException is thrown if another error occurs.

Returns:

A String representation of the value of this property.

Throws:

ValueFormatException - if conversion to a String is not possible.

java.lang.IllegalStateException - if getStream has previously been called on this Value instance.

RepositoryException - if another error occurs.

getStream

public java.io.InputStream getStream()
                              throws java.lang.IllegalStateException,
                                     RepositoryException

Returns an InputStream representation of this value. Uses the standard conversion to binary (see JCR specification)

If a non-stream get method has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getStream.

A RepositoryException is thrown if another error occurs.

Returns:

An InputStream representation of this value.

Throws:

java.lang.IllegalStateException - if a non-stream get method has previously been called on this Value instance.

RepositoryException - if another error occurs.

getLong

public long getLong()
             throws ValueFormatException,
                    java.lang.IllegalStateException,
                    RepositoryException

Returns a long representation of this value.

If this value cannot be converted to a long, a ValueFormatException is thrown.

If getStream has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getLong.

A RepositoryException is thrown if another error occurs.

Returns:

A long representation of this value.

Throws:

ValueFormatException - if conversion to an long is not possible.

java.lang.IllegalStateException - if getStream has previously been called on this Value instance.

RepositoryException - if another error occurs.

getDouble

public double getDouble()
                 throws ValueFormatException,
                        java.lang.IllegalStateException,
                        RepositoryException

Returns a double representation of this value.

If this value cannot be converted to a double, a ValueFormatException is thrown.

If getStream has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getDouble.

A RepositoryException is thrown if another error occurs.

Returns:

A double representation of this value.

Throws:

ValueFormatException - if conversion to a double is not possible.

java.lang.IllegalStateException - if getStream has previously been called on this Value instance.

RepositoryException - if another error occurs.

getDate

public java.util.Calendar getDate()
                           throws ValueFormatException,
                                  java.lang.IllegalStateException,
                                  RepositoryException

Returns a Calendar representation of this value.

The object returned is a copy of the stored value, so changes to it are not reflected in internal storage.

If this value cannot be converted to a Calendar, a ValueFormatException is thrown.

If getStream has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getDate.

A RepositoryException is thrown if another error occurs.

Returns:

A Calendar representation of this value.

Throws:

ValueFormatException - if conversion to a Calendar is not possible.

java.lang.IllegalStateException - if getStream has previously been called on this Value instance.

RepositoryException - if another error occurs.

getBoolean

public boolean getBoolean()
                   throws ValueFormatException,
                          java.lang.IllegalStateException,
                          RepositoryException

Returns a Boolean representation of this value.

If this value cannot be converted to a Boolean, a ValueFormatException is thrown.

If getStream has previously been called on this Value instance, an IllegalStateException is thrown. In this case a new Value instance must be acquired in order to successfully call getBoolean.

A RepositoryException is thrown if another error occurs.

Returns:

A Boolean representation of this value.

Throws:

ValueFormatException - if conversion to a Boolean is not possible.

java.lang.IllegalStateException - if getStream has previously been called on this Value instance.

RepositoryException - if another error occurs.

getType

public int getType()

Returns the type of this Value. One of:

• PropertyType.STRING
• PropertyType.DATE
• PropertyType.BINARY
• PropertyType.DOUBLE
• PropertyType.LONG
• PropertyType.BOOLEAN
• PropertyType.NAME
• PropertyType.PATH
• PropertyType.REFERENCE

See PropertyType.

The type returned is that which was set at property creation.