org.vishia.msgDispatch

Class LogMessageStream

java.lang.Object

org.vishia.msgDispatch.LogMessageBase

org.vishia.msgDispatch.LogMessageStream

All Implemented Interfaces:

java.lang.Appendable, LogMessage

public class LogMessageStream
extends LogMessageBase

This class adapts a given stream output channel to the LogMessage interface to output messages for example to the System.out or System.err but also to an ordinary file. In 2022-09 it is enhanced with a second channel to output twice, and also with an Appendable channel as second channel to output immediately to a StringBuilder or any other Appendable destination.
Note that Java has two concepts dealing with textual information:

• All String processing stuff uses UTF16 with 2 byte character without encoding problems. UTF16 and hence the Java String processing does not support all characters which are possible in UTF-8, but this is not an meaningful disadvantage. The advantage of UTF16 is the possible internal index calculation, any character has 2 Bytes in memory. The amount of internal memory necessary is also usual not a problem.
• All ordinary String outputs usual written to OutputStream as also the System.out and any other PrintStream uses bytes for Strings. The encoding depends on settings. Often only ASCII is expected, whereas (byte)(c) is used from c, a character. But sometimes also UTF8 is produced.
  Outputs on operation systems often uses this approach. A general usage of UTF16 for all outputs was tried to establish by some operation systems and tools, but it was not successfully. That is also because UTF-16 is limited for special character, and it is ineffective to store. Instead the UTF-8 was established.

To support both approaches Java knows both, the OutputStream and its implementations for byte-characters and the Writer and its implementations for UTF-16, and also the adequate inputs.
The Appendable is a simple interface for UTF16, implemented by the StringBuilder and also for all Writer. Hence the other possibility is the simple Appendable as output, which is checked whether it is Closable and Flushable for close and flush.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) boolean	closeOnClose If true than close() is effective for all associated channels
private java.text.SimpleDateFormat	dateFormat
(package private) java.nio.charset.Charset	encoding
(package private) java.io.FileDescriptor	fd
(package private) java.io.OutputStream	out1
(package private) java.io.OutputStream	out2
(package private) java.lang.Appendable	out3
(package private) byte[]	sNewLine Newline-String, univeral solution not for windows especially (since 2022-09, before it was \r\n.
static int	version Version, history and license.

Fields inherited from class org.vishia.msgDispatch.LogMessageBase

nLogLevel

Fields inherited from interface org.vishia.msgDispatch.LogMessage

debug, error, fineDebug, fineInfo, info, minSecondsFormat, mNeverOutputToDisplay, mReportLevel, sVersion, warning

Constructor Summary

Constructors

Constructor and Description
LogMessageStream(java.io.FileDescriptor fd) Associates the LogMessageStream with the named opened file.
LogMessageStream(java.io.OutputStream out) Associates the LogMessageStream with the named opened file.
LogMessageStream(java.io.OutputStream out1, java.io.OutputStream out2, java.lang.Appendable out3, boolean closeOnClose, java.nio.charset.Charset encoding) Associates upto three output channels, all gets the same information.

Method Summary

Modifier and Type	Method and Description
java.lang.Appendable	append(char c)
java.lang.Appendable	append(java.lang.CharSequence csq)
java.lang.Appendable	append(java.lang.CharSequence csq, int start, int end)
void	close() A call of this method closes the devices, which processed the message.
static LogMessage	create(java.io.FileDescriptor fd)
void	flush() A call of this method causes an activating of transmission of all messages since last flush.
boolean	isOnline() Checks whether the message output is available.
boolean	sendMsg(int identNumber, java.lang.CharSequence text, java.lang.Object... args) Sends a message.
boolean	sendMsgTime(int identNumber, OS_TimeStamp creationTime, java.lang.CharSequence text, java.lang.Object... args) Sends a message.
boolean	sendMsgVaList(int identNumber, OS_TimeStamp creationTime, java.lang.CharSequence text, Va_list args) Sends a message.

Methods inherited from class org.vishia.msgDispatch.LogMessageBase

flushReport, getReportLevel, getReportLevelFromIdent, report, report, reportln, reportln, setReportLevel, setReportLevelToIdent, writeError, writeError, writeInfo, writeInfoln, writeWarning

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.vishia.msgDispatch.LogMessage

msgSec, timeCurr, timeMsg

Field Detail

version

public static final int version

Version, history and license.

• 2023-02-13 Experience with stack info on messages. It is nice to know from where the message comes (srcfile, line).
• 2022-09-23 enhanced with a second channel to output twice, and also with an Appendable channel as second channel to output immediately to a StringBuilder or any other Appendable destination.
• 2009-00-00 Hartmut created to output a message via LogMessage interface simple in any opened stream.

Copyright/Copyleft: For this source the LGPL Lesser General Public License, published by the Free Software Foundation is valid. It means:

1. You can use this source without any restriction for any desired purpose.
2. You can redistribute copies of this source to everybody.
3. Every user of this source, also the user of redistribute copies with or without payment, must accept this license for further using.
4. But the LPGL ist not appropriate for a whole software product, if this source is only a part of them. It means, the user must publish this part of source, but don't need to publish the whole source of the own product.
5. You can study and modify (improve) this source for own using or for redistribution, but you have to license the modified sources likewise under this LGPL Lesser General Public License. You mustn't delete this Copyright/Copyleft inscription in this source file.

If you are intent to use this sources without publishing its usage, you can get a second license subscribing a special contract with the author.

See Also:

Constant Field Values

fd

final java.io.FileDescriptor fd

out1

final java.io.OutputStream out1

out2

final java.io.OutputStream out2

out3

final java.lang.Appendable out3

closeOnClose

final boolean closeOnClose

If true than close() is effective for all associated channels

encoding

final java.nio.charset.Charset encoding

sNewLine

byte[] sNewLine

Newline-String, univeral solution not for windows especially (since 2022-09, before it was \r\n.

dateFormat

private final java.text.SimpleDateFormat dateFormat

Constructor Detail

LogMessageStream

public LogMessageStream(java.io.FileDescriptor fd)

Associates the LogMessageStream with the named opened file. Note: The file is not closed by this instance if close() is called.

Parameters:

fd -

LogMessageStream

public LogMessageStream(java.io.OutputStream out)

Associates the LogMessageStream with the named opened file. Note: The file is not closed by this instance if close() is called.

Parameters:

fd -

LogMessageStream

public LogMessageStream(java.io.OutputStream out1,
                        java.io.OutputStream out2,
                        java.lang.Appendable out3,
                        boolean closeOnClose,
                        java.nio.charset.Charset encoding)

Associates upto three output channels, all gets the same information. This is usefull for example if a message should be seen on console (System.out) and also in a file and also in a StringBuilder for evaluation.

Parameters:

out1 - any Stream, can be null, for example System.out

out2 - any Stream, can be null, for example an opened FileOutputStream

out3 - any Appendable, can be null, can be a Closeable too.

closeOnClose - true than close() of this instance closes all associated resources

Charset - if null use the default Charset of the JVM, used for the Stream outputs. It is recommended to set null (default Charset) if System.out is used as output channel.

Method Detail

create

public static LogMessage create(java.io.FileDescriptor fd)

sendMsgVaList

public boolean sendMsgVaList(int identNumber,
                             OS_TimeStamp creationTime,
                             java.lang.CharSequence text,
                             Va_list args)

Sends a message. See interface.

Parameters:

identNumber -

creationTime -

text -

typeArgs - Type chars, ZCBSIJFD for boolean, char, byte, short, int, long, float double.

args - see interface

Returns:

true than okay. It is possible, that a destination for dispatching is not available yet. Than the routine returns false. That is for special outputs of message dispatcher. Normally the user shouldn't realize false here and react anywise. If a message isn't able to transport, it is not visible in the creating thread. It is possible that a message is lost anywhere in transportation way. In Generally, to secure a complex systems functionality, any timeouts, repeats and backup strategies are necessary in the supervise software above sending a single message.

close

public void close()

Description copied from interface: LogMessage

A call of this method closes the devices, which processed the message. It is abstract. It depends from the kind of device, what close mean. If the device is a log file writer it should be clearly. close may mean, the processing of messages is finite temporary. An open occurs automatically, if a new message is dispatched.

flush

public void flush()

Description copied from interface: LogMessage

A call of this method causes an activating of transmission of all messages since last flush. It is abstract. It depends from the kind of device, what flush mean. If the device is a log file writer it should be clearly. flush may mean, the processing of messages is ready to transmit yet.

isOnline

public boolean isOnline()

Description copied from interface: LogMessage

Checks whether the message output is available.

sendMsg

public boolean sendMsg(int identNumber,
                       java.lang.CharSequence text,
                       java.lang.Object... args)

Description copied from interface: LogMessage

Sends a message. The timestamp of the message is build with the system time. All other parameter are identically see #sendMsg(int, OS_TimeStamp, String, Object...).

Parameters:

identNumber - of the message. If it is negative, it is the same message as positive number, but with information 'going state', where the positive number is 'coming state'.

text - The text representation of the message, format string, see java.lang.String.format(..).

args - 0, 1 or more arguments of any type. The interpretation of the arguments is controlled by param text.

Returns:

true if the message will be dispatched, false if it is suppressed

sendMsgTime

public boolean sendMsgTime(int identNumber,
                           OS_TimeStamp creationTime,
                           java.lang.CharSequence text,
                           java.lang.Object... args)

Description copied from interface: LogMessage

Sends a message.

Parameters:

identNumber - of the message. If it is negative, it is the same message as positive number, but with information 'going state', where the positive number is 'coming state'.

creationTime - absolute time stamp. @Java2C=perValue.

text - The text representation of the message, format string, see java.lang.String.format(..).

args - 0, 1 or more arguments of any type. The interpretation of the arguments is controlled by param text.

Returns:

true if the message will be dispatched, false if it is suppressed

append

public java.lang.Appendable append(java.lang.CharSequence csq)
                            throws java.io.IOException

Throws:

java.io.IOException

append

public java.lang.Appendable append(java.lang.CharSequence csq,
                                   int start,
                                   int end)
                            throws java.io.IOException

Throws:

java.io.IOException

append

public java.lang.Appendable append(char c)
                            throws java.io.IOException

Throws:

java.io.IOException