So, I am making a custom plugin for my server, and one of my features requires me to set an integer in a gui that shows how many 'CommonPackages' a user has. The issue that I am having is that when I am getting the String from my config (My config uses a custom file creation/management class that was given to me by a friend) it is saying that it is null in the gui, I do not get any errors in the console, please may someone help me? The item in the gui and the code for setting the item in the gui.
Item in the gui
gui creation code:
public static Inventory WhiteBackpack(Player player) {
UUID uuid = player.getUniqueId();
Inventory inv = Bukkit.createInventory(null, 27, (inventoryname));
ItemStack common = new ItemStack(Material.INK_SACK);
common.setDurability((byte) 8);
ItemMeta commonMeta = common.getItemMeta();
commonMeta.setDisplayName(Utils.chat("&fCommon Packages &8» &f&l" + Main.pl.getFileControl().getConfig().getString("players." + uuid + ".Packages.Common"))); //How I access my custom configs.
common.setItemMeta(commonMeta);
inv.setItem(10, common);
return inv;
}
Without the code of your method to get the config I can only say that the string in the actual file is not present.
As the Bukkit documentation states:
If the String does not exist and no default value was specified, this will return null.
So either the key just does not exist in the file or you pointed to the wrong file. The configuration should be well formated, too. (no tabs, only spaces)
I want Administrators to enable/disable logging at runtime by changing the enabled property of the LogEnabledFilter in the config.
There are several threads on SO that explain workarounds, but I want it this way.
I tried to change the Logging Enabled Filter like this:
private static void FileConfigurationSourceChanged(object sender, ConfigurationSourceChangedEventArgs e)
{
var fcs = sender as FileConfigurationSource;
System.Diagnostics.Debug.WriteLine("----------- FileConfigurationSourceChanged called --------");
LoggingSettings currentLogSettings = e.ConfigurationSource.GetSection("loggingConfiguration") as LoggingSettings;
var fdtl = currentLogSettings.TraceListeners.Where(tld => tld is FormattedDatabaseTraceListenerData).FirstOrDefault();
var currentLogFileFilter = currentLogSettings.LogFilters.Where(lfd => { return lfd.Name == "Logging Enabled Filter"; }).FirstOrDefault();
var filterNewValue = (bool)currentLogFileFilter.ElementInformation.Properties["enabled"].Value;
var runtimeFilter = Logger.Writer.GetFilter<LogEnabledFilter>("Logging Enabled Filter");
runtimeFilter.Enabled = filterNewValue;
var test = Logger.Writer.IsLoggingEnabled();
}
But test reveals always the initially loaded config value, it does not change.
I thought, that when changing the value in the config the changes will be propagated automatically to the runtime configuration. But this isn't the case!
Setting it programmatically as shown in the code above, doesn't work either.
It's time to rebuild Enterprise Library or shut it down.
You are right that the code you posted does not work. That code is using a config file (FileConfigurationSource) as the method to configure Enterprise Library.
Let's dig a bit deeper and see if programmatic configuration will work.
We will use the Fluent API since it is the preferred method for programmatic configuration:
var builder = new ConfigurationSourceBuilder();
builder.ConfigureLogging()
.WithOptions
.DoNotRevertImpersonation()
.FilterEnableOrDisable("EnableOrDisable").Enable()
.LogToCategoryNamed("General")
.WithOptions.SetAsDefaultCategory()
.SendTo.FlatFile("FlatFile")
.ToFile(#"fluent.log");
var configSource = new DictionaryConfigurationSource();
builder.UpdateConfigurationWithReplace(configSource);
var defaultWriter = new LogWriterFactory(configSource).Create();
defaultWriter.Write("Test1", "General");
var filter = defaultWriter.GetFilter<LogEnabledFilter>();
filter.Enabled = false;
defaultWriter.Write("Test2", "General");
If you try this code the filter will not be updated -- so another failure.
Let's try to use the "old school" programmatic configuration by using the classes directly:
var flatFileTraceListener = new FlatFileTraceListener(
#"program.log",
"----------------------------------------",
"----------------------------------------"
);
LogEnabledFilter enabledFilter = new LogEnabledFilter("Logging Enabled Filter", true);
// Build Configuration
var config = new LoggingConfiguration();
config.AddLogSource("General", SourceLevels.All, true)
.AddTraceListener(flatFileTraceListener);
config.Filters.Add(enabledFilter);
LogWriter defaultWriter = new LogWriter(config);
defaultWriter.Write("Test1", "General");
var filter = defaultWriter.GetFilter<LogEnabledFilter>();
filter.Enabled = false;
defaultWriter.Write("Test2", "General");
Success! The second ("Test2") message was not logged.
So, what is going on here? If we instantiate the filter ourselves and add it to the configuration it works but when relying on the Enterprise Library configuration the filter value is not updated.
This leads to a hypothesis: when using Enterprise Library configuration new filter instances are being returned each time which is why changing the value has no effect on the internal instance being used by Enterprise Library.
If we dig into the Enterprise Library code we (eventually) hit on LoggingSettings class and the BuildLogWriter method. This is used to create the LogWriter. Here's where the filters are created:
var filters = this.LogFilters.Select(tfd => tfd.BuildFilter());
So this line is using the configured LogFilterData and calling the BuildFilter method to instantiate the applicable filter. In this case the BuildFilter method of the configuration class LogEnabledFilterData BuildFilter method returns an instance of the LogEnabledFilter:
return new LogEnabledFilter(this.Name, this.Enabled);
The issue with this code is that this.LogFilters.Select returns a lazy evaluated enumeration that creates LogFilters and this enumeration is passed into the LogWriter to be used for all filter manipulation. Every time the filters are referenced the enumeration is evaluated and a new Filter instance is created! This confirms the original hypothesis.
To make it explicit: every time LogWriter.Write() is called a new LogEnabledFilter is created based on the original configuration. When the filters are queried by calling GetFilter() a new LogEnabledFilter is created based on the original configuration. Any changes to the object returned by GetFilter() have no affect on the internal configuration since it's a new object instance and, anyway, internally Enterprise Library will create another new instance on the next Write() call anyway.
Firstly, this is just plain wrong but it is also inefficient to create new objects on every call to Write() which could be invoked many times..
An easy fix for this issue is to evaluate the LogFilters enumeration by calling ToList():
var filters = this.LogFilters.Select(tfd => tfd.BuildFilter()).ToList();
This evaluates the enumeration only once ensuring that only one filter instance is created. Then the GetFilter() and update filter value approach posted in the question will work.
Update:
Randy Levy provided a fix in his answer above.
Implement the fix and recompile the enterprise library.
Here is the answer from Randy Levy:
Yes, you can disable logging by setting the LogEnabledFiter. The main
way to do this would be to manually edit the configuration file --
this is the main intention of that functionality (developers guide
references administrators tweaking this setting). Other similar
approaches to setting the filter are to programmatically modify the
original file-based configuration (which is essentially a
reconfiguration of the block), or reconfigure the block
programmatically (e.g. using the fluent interface). None of the
programmatic approaches are what I would call simple – Randy Levy 39
mins ago
If you try to get the filter and disable it I don't think it has any
affect without a reconfiguration. So the following code still ends up
logging: var enabledFilter = logWriter.GetFilter();
enabledFilter.Enabled = false; logWriter.Write("TEST"); One non-EntLib
approach would just to manage the enable/disable yourself with a bool
property and a helper class. But I think the priority approach is a
pretty straight forward alternative.
Conclusion:
In your custom Logger class implement a IsLoggenabled property and change/check this one at runtime.
This won't work:
var runtimeFilter = Logger.Writer.GetFilter<LogEnabledFilter>("Logging Enabled Filter");
runtimeFilter.Enabled = false/true;
I am looking to open up multiple connections using a netty client bootstrap in order to parse messages coming from multiple sources. The messages all have the same format, however, due to the amount of data that needs to be processed, I must run each connection on separate threads (This is assuming netty creates a thread per client channel, which I couldn't find a reference for - if that's not the case, how would this be achieved?).
This is the code that I use to connect to the data server:
var b = new Bootstrap()
.group(group)
.channel(classOf[NioSocketChannel])
.handler(RawFeedChannelInitializer)
var ch1 = b.clone().connect(host, port).sync().channel();
var ch2 = b.clone().connect(host, port).sync().channel();
The initializer calls RawPacketDecoder, which extends ReplayingDecoder, and is defined here.
The code works well without #Sharable when opening a single connection, but for the purpose of my application I must connect to the same server multiple times.
This results in the runtime error #Sharable annotation is not allowed pointing to my RawPacketDecoder class.
I am not entirely sure on how to get past this issue, short of reimplementing in scala an instantiable class of ReplayingDecoder as my decoder based directly on ByteToMessageDecoder.
Any help would be greatly appreciated.
Note: I am using netty 4.0.32 Final
I found the solution in this StockExchange answer.
My issue was that I was using an object based ChannelInitializer (singleton), and ReplayingDecoder as well as ByteToMessageDecoder are not sharable.
My initializer was created as a scala object, and therefore a single instance allowed. Changing the initializer to a scala class and instantiating for each bootstrap clone solved the problem. I modified the bootstrap code above as follows:
var b = new Bootstrap()
.group(group)
.channel(classOf[NioSocketChannel])
//.handler(RawFeedChannelInitializer)
var ch1 = b.clone().handler(new RawFeedChannelInitializer()).connect(host, port).sync().channel();
var ch2 = b.clone().handler(new RawFeedChannelInitializer()).connect(host, port).sync().channel();
I am not sure whether this ensures multithreading as wanted but it does allow to split the data access into multiple connections to the feed server.
Edit Update: After performing additional research on the subject, I have determined that netty does in fact create a thread per channel; this was verified by printing to console after the creation of each channel:
println("No. of active threads: " + Thread.activeCount());
The output shows an incremental number as channels are created and associated with their respective threads.
By default NioEventLoopGroup uses 2*Num_CPU_cores threads as defined here:
DEFAULT_EVENT_LOOP_THREADS = Math.max(1, SystemPropertyUtil.getInt(
"io.netty.eventLoopThreads",
Runtime.getRuntime().availableProcessors() * 2));
This value can be overriden to something else by setting
val group = new NioEventLoopGroup(16)
and then using the group to create/setup the bootstrap.
I have a very weird problem with Unity here. I have the following:
public class UnityConfig
{
public static void RegisterTypes(IUnityContainer container)
container.RegisterType<IDBContext, MyDbContext>(new PerThreadLifetimeManager());
container.RegisterType<IUserDbContext>(new PerThreadLifetimeManager(), new InjectionFactory(c =>
{
var tenantConnectionString = c.Resolve<ITenantConnectionResolver>().ResolveConnectionString();
return new UserDbContext(tenantConnectionString);
}));
}
}
and then in the WebApiConfig.cs file within the Reigster method:
var container = new UnityContainer();
UnityConfig.RegisterTypes(container);
config.DependencyResolver = new UnityResolver(container);
Basically, what I want to happen in the above code is on every request to the API, I want Unity to new up a UserDbContext based on the user (multi-tenant kind of environment). Now the TenantConnectionResolver is responsible for figuring out the Connection String and then I use that connection string to new up UserDbContext.
Also note (not shown above) that TenantConnectionResolver takes an IDbConext in its constructor because I need it to figure out the connection string based on user information in that database.
But for some reason, the code within the InjectionFactory runs at random times. For example, I call //mysite.com/controller/action/1 repetitively from a browser, the code in the InjectionFactory will occasionally run but not on each request.
Am I incorrectly configuring Unity? Has anybody encountered anything similar to this?
Thanks in advance
The problem is very likely related to the LifetimeManager you are using. PerThreadLifetimeManager is not adapted in a web context, as threads are pooled and will serve multiple requests in sequence.
PerRequestLifetimeManager is probably what you want to use.
How can I change the current working directory from within a Java program? Everything I've been able to find about the issue claims that you simply can't do it, but I can't believe that that's really the case.
I have a piece of code that opens a file using a hard-coded relative file path from the directory it's normally started in, and I just want to be able to use that code from within a different Java program without having to start it from within a particular directory. It seems like you should just be able to call System.setProperty( "user.dir", "/path/to/dir" ), but as far as I can figure out, calling that line just silently fails and does nothing.
I would understand if Java didn't allow you to do this, if it weren't for the fact that it allows you to get the current working directory, and even allows you to open files using relative file paths....
There is no reliable way to do this in pure Java. Setting the user.dir property via System.setProperty() or java -Duser.dir=... does seem to affect subsequent creations of Files, but not e.g. FileOutputStreams.
The File(String parent, String child) constructor can help if you build up your directory path separately from your file path, allowing easier swapping.
An alternative is to set up a script to run Java from a different directory, or use JNI native code as suggested below.
The relevant OpenJDK bug was closed in 2008 as "will not fix".
If you run your legacy program with ProcessBuilder, you will be able to specify its working directory.
There is a way to do this using the system property "user.dir". The key part to understand is that getAbsoluteFile() must be called (as shown below) or else relative paths will be resolved against the default "user.dir" value.
import java.io.*;
public class FileUtils
{
public static boolean setCurrentDirectory(String directory_name)
{
boolean result = false; // Boolean indicating whether directory was set
File directory; // Desired current working directory
directory = new File(directory_name).getAbsoluteFile();
if (directory.exists() || directory.mkdirs())
{
result = (System.setProperty("user.dir", directory.getAbsolutePath()) != null);
}
return result;
}
public static PrintWriter openOutputFile(String file_name)
{
PrintWriter output = null; // File to open for writing
try
{
output = new PrintWriter(new File(file_name).getAbsoluteFile());
}
catch (Exception exception) {}
return output;
}
public static void main(String[] args) throws Exception
{
FileUtils.openOutputFile("DefaultDirectoryFile.txt");
FileUtils.setCurrentDirectory("NewCurrentDirectory");
FileUtils.openOutputFile("CurrentDirectoryFile.txt");
}
}
It is possible to change the PWD, using JNA/JNI to make calls to libc. The JRuby guys have a handy java library for making POSIX calls called jnr-posix. Here's the maven info
As mentioned you can't change the CWD of the JVM but if you were to launch another process using Runtime.exec() you can use the overloaded method that lets you specify the working directory. This is not really for running your Java program in another directory but for many cases when one needs to launch another program like a Perl script for example, you can specify the working directory of that script while leaving the working dir of the JVM unchanged.
See Runtime.exec javadocs
Specifically,
public Process exec(String[] cmdarray,String[] envp, File dir) throws IOException
where dir is the working directory to run the subprocess in
If I understand correctly, a Java program starts with a copy of the current environment variables. Any changes via System.setProperty(String, String) are modifying the copy, not the original environment variables. Not that this provides a thorough reason as to why Sun chose this behavior, but perhaps it sheds a little light...
The working directory is a operating system feature (set when the process starts).
Why don't you just pass your own System property (-Dsomeprop=/my/path) and use that in your code as the parent of your File:
File f = new File ( System.getProperty("someprop"), myFilename)
The smarter/easier thing to do here is to just change your code so that instead of opening the file assuming that it exists in the current working directory (I assume you are doing something like new File("blah.txt"), just build the path to the file yourself.
Let the user pass in the base directory, read it from a config file, fall back to user.dir if the other properties can't be found, etc. But it's a whole lot easier to improve the logic in your program than it is to change how environment variables work.
I have tried to invoke
String oldDir = System.setProperty("user.dir", currdir.getAbsolutePath());
It seems to work. But
File myFile = new File("localpath.ext");
InputStream openit = new FileInputStream(myFile);
throws a FileNotFoundException though
myFile.getAbsolutePath()
shows the correct path.
I have read this. I think the problem is:
Java knows the current directory with the new setting.
But the file handling is done by the operation system. It does not know the new set current directory, unfortunately.
The solution may be:
File myFile = new File(System.getPropety("user.dir"), "localpath.ext");
It creates a file Object as absolute one with the current directory which is known by the JVM. But that code should be existing in a used class, it needs changing of reused codes.
~~~~JcHartmut
You can use
new File("relative/path").getAbsoluteFile()
after
System.setProperty("user.dir", "/some/directory")
System.setProperty("user.dir", "C:/OtherProject");
File file = new File("data/data.csv").getAbsoluteFile();
System.out.println(file.getPath());
Will print
C:\OtherProject\data\data.csv
You can change the process's actual working directory using JNI or JNA.
With JNI, you can use native functions to set the directory. The POSIX method is chdir(). On Windows, you can use SetCurrentDirectory().
With JNA, you can wrap the native functions in Java binders.
For Windows:
private static interface MyKernel32 extends Library {
public MyKernel32 INSTANCE = (MyKernel32) Native.loadLibrary("Kernel32", MyKernel32.class);
/** BOOL SetCurrentDirectory( LPCTSTR lpPathName ); */
int SetCurrentDirectoryW(char[] pathName);
}
For POSIX systems:
private interface MyCLibrary extends Library {
MyCLibrary INSTANCE = (MyCLibrary) Native.loadLibrary("c", MyCLibrary.class);
/** int chdir(const char *path); */
int chdir( String path );
}
The other possible answer to this question may depend on the reason you are opening the file. Is this a property file or a file that has some configuration related to your application?
If this is the case you may consider trying to load the file through the classpath loader, this way you can load any file Java has access to.
If you run your commands in a shell you can write something like "java -cp" and add any directories you want separated by ":" if java doesnt find something in one directory it will go try and find them in the other directories, that is what I do.
Use FileSystemView
private FileSystemView fileSystemView;
fileSystemView = FileSystemView.getFileSystemView();
currentDirectory = new File(".");
//listing currentDirectory
File[] filesAndDirs = fileSystemView.getFiles(currentDirectory, false);
fileList = new ArrayList<File>();
dirList = new ArrayList<File>();
for (File file : filesAndDirs) {
if (file.isDirectory())
dirList.add(file);
else
fileList.add(file);
}
Collections.sort(dirList);
if (!fileSystemView.isFileSystemRoot(currentDirectory))
dirList.add(0, new File(".."));
Collections.sort(fileList);
//change
currentDirectory = fileSystemView.getParentDirectory(currentDirectory);