com.goldencode.p2j.main

Class ClientCore

java.lang.Object

com.goldencode.p2j.main.ClientCore

public class ClientCore
extends java.lang.Object

Core looping logic that performs initialization of a client UI and establishes a session with the server.

This code provides supports the startup of a client session within the same process as the server. This can be used to duplicate the traditional Progress 4GL fat client approach (a "single process" mode). It can also be used to implement multiple client sessions within a true server process which would be used to support web-based clients.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ClientCore.InitStruct Structure used for passing several values to and from initialize(InitStruct, BootstrapConfig, String) method.

Field Summary

Fields

Modifier and Type	Field and Description
private static CentralLogger	LOG Logger.
private static boolean	nativeLayerInitialized Flag to prevent multiple native library loading.

Constructor Summary

Constructors

Constructor and Description
ClientCore()

Method Summary

Modifier and Type	Method and Description
private static BootstrapConfig	buildTemporaryClientConfig(BootstrapConfig config) Build a separate BootstrapConfig for temporary clients.
private static int	getLinuxScreenColorDepth() Returns the found screen color depth in Linux.
private static java.lang.String	getOsDeviceId() Returns the OS specific device ID.
static long	getPid() Native call to read the operating system pid for the current JVM process.
static java.lang.String	getUserName() Native call to read the operating system user name for the current JVM process.
static void	initialize(ClientCore.InitStruct is, BootstrapConfig config, java.lang.String uuid) Initialize client.
static boolean	isCauseStop(java.lang.Throwable chained) Inspect the chain of exceptions and report if any of them are STOP conditions.
static boolean	isNativeLayerInitialized() Returns a flag to indicate if native library has loaded.
static void	loadNativeLibrary() Loads native library and performs required initial steps for P2J library to working.
(package private) static void	outputDiagnostics(BootstrapConfig config, java.util.function.Supplier<java.lang.String> diagnostics) Render the diagnostics as text and output this to the log.
private static ClientParameters	processClientParams(ScreenDriver<?> driver, BootstrapConfig config) Pull the client parameters from the driver and bootstrap configuration and initialize a parameters object with the resulting data.
static void	processInit() Native call to set up and redefine signal processing handlers.
static ScreenDriver<?>	processTemporaryClient(java.lang.String uuid, BootstrapConfig config, java.util.function.Supplier<java.lang.String> diag) Establish a direct connection using the temporary credentials and perform custom work, depending on the TemporaryClient implementation returned by Spawner.getTemporaryClient(java.lang.String, java.lang.String).
static void	setOutputToFile(BootstrapConfig config) Reads server:clientConfig:outputToFile config from BootstrapConfig, replaces the placeholder %pid% with the current process id and redirects stdout to the file path defined as outputToFile.
static void	start(BootstrapConfig config, java.util.function.Supplier<java.lang.String> diag) Start the client loop.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final CentralLogger LOG

Logger.

nativeLayerInitialized

private static boolean nativeLayerInitialized

Flag to prevent multiple native library loading.

Constructor Detail

ClientCore

public ClientCore()

Method Detail

isNativeLayerInitialized

public static boolean isNativeLayerInitialized()

Returns a flag to indicate if native library has loaded.

Returns:

A flag to indicate if native library has loaded.

initialize

public static void initialize(ClientCore.InitStruct is,
                              BootstrapConfig config,
                              java.lang.String uuid)

Initialize client.

Parameters:

is - initialization structure in/out.

config - The configuration to use for setup of the client and for the server connection.

uuid - server:spawner:uuid configuration value

start

public static void start(BootstrapConfig config,
                         java.util.function.Supplier<java.lang.String> diag)
                  throws java.lang.Exception

Start the client loop. This will not return until the user is exiting the client. The core loop initializes logging, the security manager, the UI and then tries to connect to the server. During the connection attempt the server will send down a login screen or if guest access is enabled, the login will be bypassed. Once login has occurred (or been bypassed), the session is established and the directory manager and the UI client finish initialization. Finally the main application entry point is called on the server. The server will not return from that call until the user asks to quit, a CTRL-C occurs (stop condition) or some abnormal end occurs. Any of these cases cause the loop to terminate and this method will then return.

Parameters:

config - The configuration to use for setup of the client and for the server connection.

diag - Details about the driver state that can help diagnose server startup issues.

Throws:

java.lang.Exception

isCauseStop

public static boolean isCauseStop(java.lang.Throwable chained)

Inspect the chain of exceptions and report if any of them are STOP conditions.

Parameters:

chained - The top of the chain of exceptions.

Returns:

true if any of the exceptions in the chain are STOP conditions.

setOutputToFile

public static void setOutputToFile(BootstrapConfig config)

Reads server:clientConfig:outputToFile config from BootstrapConfig, replaces the placeholder %pid% with the current process id and redirects stdout to the file path defined as outputToFile.

Parameters:

config - Reference to the configuration reader.

loadNativeLibrary

public static void loadNativeLibrary()

Loads native library and performs required initial steps for P2J library to working.

processInit

public static void processInit()

Native call to set up and redefine signal processing handlers.

getPid

public static long getPid()

Native call to read the operating system pid for the current JVM process.

Returns:

see above

getUserName

public static java.lang.String getUserName()

Native call to read the operating system user name for the current JVM process.

Returns:

see above

outputDiagnostics

static void outputDiagnostics(BootstrapConfig config,
                              java.util.function.Supplier<java.lang.String> diagnostics)

Render the diagnostics as text and output this to the log.

Parameters:

config - The bootstrap configuration for this client.

diagnostics - Details about the client process.

buildTemporaryClientConfig

private static BootstrapConfig buildTemporaryClientConfig(BootstrapConfig config)

Build a separate BootstrapConfig for temporary clients.

Parameters:

config - Client bootstrap configuration.

Returns:

A new BootstrapConfig configured for temporary client connections.

processClientParams

private static ClientParameters processClientParams(ScreenDriver<?> driver,
                                                    BootstrapConfig config)

Pull the client parameters from the driver and bootstrap configuration and initialize a parameters object with the resulting data.

Parameters:

driver - The primary UI driver for this client session.

config - The bootstrap configuration for this session (this must have been previously merged with any command line overrides).

Returns:

The configured parameters object.

processTemporaryClient

public static ScreenDriver<?> processTemporaryClient(java.lang.String uuid,
                                                     BootstrapConfig config,
                                                     java.util.function.Supplier<java.lang.String> diag)
                                              throws java.lang.Exception

Establish a direct connection using the temporary credentials and perform custom work, depending on the TemporaryClient implementation returned by Spawner.getTemporaryClient(java.lang.String, java.lang.String).

Parameters:

uuid - Remote client identifier uuid.

config - The configuration to use for setup of the client and for the server connection.

diag - Details about the driver state that can help diagnose server startup issues.

Returns:

The screen driver returned by TemporaryClient.doWork(com.goldencode.p2j.main.Spawner, com.goldencode.p2j.cfg.BootstrapConfig, java.util.function.Supplier<java.lang.String>).

Throws:

java.lang.Exception - If something goes wrong.

getOsDeviceId

private static java.lang.String getOsDeviceId()

Returns the OS specific device ID.

Returns:

The found device ID.

getLinuxScreenColorDepth

private static int getLinuxScreenColorDepth()

Returns the found screen color depth in Linux.

Returns:

See above.