net.sf.eBus.messages

Class EMessageObject.Builder<M extends EMessageObject,B extends EMessageObject.Builder<M,?>>

java.lang.Object

net.sf.eBus.messages.EMessageObject.Builder<M,B>

Type Parameters:

M - builds this target message class.

B - message builder subclass. Needed to return the correct builder type when setting fields. If this were not the case, field chaining would not work.

Direct Known Subclasses:

EField.Builder, EMessage.Builder

Enclosing class:

EMessageObject

public abstract static class EMessageObject.Builder<M extends EMessageObject,B extends EMessageObject.Builder<M,?>>
extends Object

Base class for all EMessageObject builders. Used by eBus when de-serializing an encoded message back into the target message object.

Field Summary

Fields

Modifier and Type	Field and Description
protected Class<? extends EMessageObject>	mTargetClass Message class instance returned by build().

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Builder(Class<? extends EMessageObject> targetClass)

Method Summary

Modifier and Type	Method and Description
M	build() Returns the target message instance constructed from the configured properties.
protected abstract M	buildImpl() Returns eBus message instance built from the configured properties.
protected void	validate(List<String> problems) Checks if message subject and message type are configured.

Methods inherited from class java.lang.Object

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

Field Detail

mTargetClass

protected final Class<? extends EMessageObject> mTargetClass

Message class instance returned by build(). This value is used to identify the target class when a build failure occurs, placed into the ValidationException.

Constructor Detail

Builder

protected Builder(Class<? extends EMessageObject> targetClass)

Method Detail

buildImpl

protected abstract M buildImpl()

Returns eBus message instance built from the configured properties. Note: the builder configuration was validated prior to calling this method. The message object may now be constructed.

Returns:

target message class instance.

validate

protected void validate(List<String> problems)

Checks if message subject and message type are configured. If not, then text explaining this error is appended to problems.

This method should be overridden by subclass message builders and called before doing its own validation. The first line in the subclass validate implementation should be super.validate(problems);.

When overriding this method, be sure to add all discovered validation problems to the list. The validation method should consist of a series of individual if statements and not an if/else if chain. That way all problems are found and not just the first one.

Parameters:

problems - append validation problems to this list.

build

public final M build()
              throws ValidationException

Returns the target message instance constructed from the configured properties. This must be the final method in a builder configuration call chain.

Returns:

target message instance.

Throws:

ValidationException - if this builder does not contain a valid target message configuration. This exception contains a list of all validation problems found.