Package com.composum.sling.core.logging

Class MessageContainer

java.lang.Object

com.composum.sling.core.logging.MessageContainer

All Implemented Interfaces:

Iterable<Message>

@ThreadSafe
public class MessageContainer
extends Object
implements Iterable<Message>

A collection of Messages for humans - also meant for transmitting them via JSON.

Field Summary

Fields

Modifier and Type	Field	Description
protected Object	lockObject	Synchronizing on this when accessing messages.
protected @Nullable org.slf4j.Logger	log	A logger where add(Message) automatically logs to.
protected static Comparator<Message>	MESSAGE_TIME_COMPARATOR	Used to sort messages by their time.
protected @Nullable List<Message>	messages

Constructor Summary

Constructors

Constructor	Description
MessageContainer()	Default constructor which means we do not log added messages - usually it's better to use MessageContainer(Logger) and log things immediately.
MessageContainer(@Nullable org.slf4j.Logger log)	Constructor that allows to set a logger to which add(Message) automatically writes the messages.

Method Summary

Modifier and Type	Method	Description
@NotNull MessageContainer	add(@Nullable Message message)	Adds a message to the container, and logs it into the logger if one was specified for this container.
@NotNull MessageContainer	add(@Nullable Message message, @Nullable Throwable throwable)	Adds a message to the container, and logs it into the logger if one was specified for this container.
@NotNull MessageContainer	addAll(@Nullable MessageContainer messageContainer)	Adds all messages of a MessageContainer to this container.
@NotNull MessageContainer	clear()	Removes all messages.
void	forEach(Consumer<? super Message> action)	Iterates over a readonly view.
@NotNull List<Message>	getMessages()	A (unmodifiable) snapshot of the list of messages.
boolean	hasError()	True if a MessageContainer contains a message with an Message.error(java.lang.String, java.lang.Object...).
boolean	isEmpty()	Whether there are any messages.
Iterator<Message>	iterator()	Iterates over a readonly view.
void	logInto(@Nullable org.slf4j.Logger logger)	Logs the messages into the given container.
void	setLogger(org.slf4j.Logger logger)	Modifies the logger newly add(Message)-ed / add(Message, Throwable)-ed messages are logged to.
Spliterator<Message>	spliterator()	Iterates over a readonly view.

Methods inherited from class java.lang.Object

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

Field Detail

MESSAGE_TIME_COMPARATOR

protected static final Comparator<Message> MESSAGE_TIME_COMPARATOR

Used to sort messages by their time.

log

@Nullable
protected transient volatile @Nullable org.slf4j.Logger log

A logger where add(Message) automatically logs to.

lockObject

protected final transient Object lockObject

Synchronizing on this when accessing messages.

messages

@Nullable
protected @Nullable List<Message> messages

See Also:

getMessages()

Constructor Detail

MessageContainer

public MessageContainer()

Default constructor which means we do not log added messages - usually it's better to use MessageContainer(Logger) and log things immediately.

MessageContainer

public MessageContainer(@Nullable
                        @Nullable org.slf4j.Logger log)

Constructor that allows to set a logger to which add(Message) automatically writes the messages.

Parameters:

log - an optional log to which added messages are logged.

Method Detail

getMessages

@NotNull
public @NotNull List<Message> getMessages()

A (unmodifiable) snapshot of the list of messages.

add

@NotNull
public @NotNull MessageContainer add(@Nullable
                                     @Nullable Message message,
                                     @Nullable
                                     @Nullable Throwable throwable)

Adds a message to the container, and logs it into the logger if one was specified for this container. The intended usecase is with a logger, so we log a warning if it's called with a throwable but we have no logger, so that Stacktraces don't disappear accidentially.

Returns:

this MessageContainer, for builder-style operation chaining.

add

@NotNull
public @NotNull MessageContainer add(@Nullable
                                     @Nullable Message message)

Adds a message to the container, and logs it into the logger if one was specified for this container. Like in SLF4J, if the last argument is a Throwable we use it for logging with add(Message, Throwable).

Returns:

this MessageContainer, for builder-style operation chaining.

addAll

@NotNull
public @NotNull MessageContainer addAll(@Nullable
                                        @Nullable MessageContainer messageContainer)

Adds all messages of a MessageContainer to this container.

logInto

public void logInto(@Nullable
                    @Nullable org.slf4j.Logger logger)

Logs the messages into the given container. This is automatically done on add(Message) if a logger is set, but this might be necessary after deserializing the container.

clear

@NotNull
public @NotNull MessageContainer clear()

Removes all messages.

Returns:

this MessageContainer, for builder-style operation chaining.

isEmpty

public boolean isEmpty()

Whether there are any messages.

hasError

public boolean hasError()

True if a MessageContainer contains a message with an Message.error(java.lang.String, java.lang.Object...).

iterator

public Iterator<Message> iterator()

Iterates over a readonly view.

Specified by:

iterator in interface Iterable<Message>

forEach

public void forEach(Consumer<? super Message> action)

Iterates over a readonly view.

Specified by:

forEach in interface Iterable<Message>

spliterator

public Spliterator<Message> spliterator()

Iterates over a readonly view.

Specified by:

spliterator in interface Iterable<Message>

setLogger

public void setLogger(org.slf4j.Logger logger)

Modifies the logger newly add(Message)-ed / add(Message, Throwable)-ed messages are logged to.