Based on this question, I'm trying to switch to the version 3.5-EA of Hibernate.
Up to now I had a configuration like this:
CacheConfiguration<K, V> configuration = new CacheConfig<K, V>()
.setNearCacheConfig(new NearCacheConfig().setInMemoryFormat(InMemoryFormat.OBJECT))
.setExpiryPolicyFactory(createExpiryPolicyFactory(expiryDuration));
cache = cacheManager.createCache(cacheName, configuration);
But now the setNearCacheConfig method is gone. There only exists a addNearCacheConfig on the ClientCacheConfig. But I don't have a ClientCacheConfig.
I basically don't know where to put the NearCacheConfig.
the configuration of the nearcache can be done on the client side. http://docs.hazelcast.org/docs/3.5/manual/html-single/hazelcast-documentation.html#hazelcast-java-client
If you do not want to use xml for configuration (http://docs.hazelcast.org/docs/latest/manual/html-single/hazelcast-documentation.html#near-cache) - you could probably do something like this -
Config cfg = new Config();
MapConfig mc = new MapConfig();
mc.setNearCacheConfig(new NearCacheConfig());
cfg.addMapConfig(mc);
HazelcastInstance hi = Hazelcast.newHazelcastInstance(cfg);
As per my opinion, NearCache feature is useful when you are using Client-Server hazelcast api and when youa re trying to access cache externally, but if you are gonna make call within hazelcast cluster internally and do not want to use Hazelcast client api than there no need to use NearCache feature.
Since there will not be any benefit out of it.
Related
I get this error because I have circular references defined in my object model. My question is, is there any way to resolve this using one of the following two options?
Using Newtonsoft.Json and options.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
Using System.Text.Json and options.JsonSerializerOptions.ReferenceHandler = System.Text.Json.Serialization.ReferenceHandler.Preserve;
I'm not seeing a way to switch to Newtonsoft.Json in a Blazor WebAssembly application and I tried implementing option 2 in the ConfigureServices function of Startup.cs in my Server project but I still kept getting the error.
I'm just trying to find a solution that doesn't require me redefining my object model. The JsonIgnore attribute does not appear to be an option either because I assume, and it appears, that then any fields I define it on do not exist in the Json on the client which breaks my application.
Update: I found this site which looks to me like discusses exactly what I'm referring to here and how to implement the solution but I have not got it to work yet. If anyone is successfully using Blazor WebAssembly with circular references in your object model please let me know what you're doing.
https://github.com/dotnet/aspnetcore/issues/28286
Thank you for pointing out this error in Blazor. I found the answer in the issue you mentioned (this comment). You need to change json options also on the Client side. This works for me:
On server
services.AddControllersWithViews().AddJsonOptions(options =>
{
options.JsonSerializerOptions.ReferenceHandler = System.Text.Json.Serialization.ReferenceHandler.Preserve;
options.JsonSerializerOptions.PropertyNamingPolicy = null;
});
On client
var response = await Http.GetFromJsonAsync<T>("{Address}", new JsonSerializerOptions
{
ReferenceHandler = System.Text.Json.Serialization.ReferenceHandler.Preserve,
PropertyNamingPolicy = null
});
To the two options you mentioned there is a third option available if you use .NET 6 or above.
Using System.Text.Json and options.JsonSerializerOptions.ReferenceHandler = ReferenceHandler.IgnoreCycles;
Beware that ignoring cycles have issues on its own (such as data corruption) but if you were depending on it when you were using Newtonsoft.Json then you will be fine as it is basically the same behavior.
If you prefer to go with ReferenceHandler.Preserve, please share more info on what error you are getting and I can try to help you out.
One way to go about this is specify how much depth an object is allowed to have. Please see the documentation here regarding how to do this with System.Text.Json. I think this may help.
I am migrating a console app (REST client app) from .NET framework to .NET Core.
In my current (framework) version, I use the app.config file to set the System.Net configuration:
<system.net>
<connectionManagement>
<add address="*" maxconnection="65535"/>
</connectionManagement>
</system.net>
In .NET Core, I have to use a JSON file for configuration. There is no documentation for implementing these settings using the new configuration schema. Does anyone know how this might look inside the new JSON config, or the correct way to implement this in Core? Do I need to build a designated "System.Net.json" config file (separate from an AppSettings.json) specifically to do this?
Thanks.
I assume you're trying to avoid the limit of 2 connections per endpoint, which is default on .NET Framework. Such limit does not exist on .NET Core. So you don't need the above setting at all.
Note that to achieve better perf, we recommend to use HttpClient/HttpClientHandler over HttpWebRequest/ServicePoint on .NET Core. HttpWebRequest/ServicePoint APIs are compat-only.
If you want to limit HttpClient connections, then use HttpClientHandler.MaxConnectionsPerServer
Assuming you are using Kestrel as your web server (and not doing it through IIS implementation), you should be able to set this in your UseKestrel in your BuildWebHost.
It would go something like this:
.UseKestrel(options =>
{
options.Limits.MaxConcurrentConnections = 100;
})
You can also add this in your HttpClientHandler, It's called MaxConnectionsPerServer. It can be seen here.
Some addition to Karel Zikmund answer. (As i don’t have permissions to comment).
According to this doc connections are limited since .net core 2.0:
https://learn.microsoft.com/en-us/dotnet/api/system.net.servicepointmanager.defaultconnectionlimit?view=netcore-3.1
What is missed in doc is if ServicePointManager used for .net core HttpClient implementation. According to this info it is used in .net core, but for HttpWebRequest, not HttpClient: https://github.com/dotnet/runtime/issues/26048
Frameworks like Spring, Struts facilitates for property file reading. For instance MessageResources in Struts. I want to know whether there are such property files which are in built supported by Restlet framework itself. If there is one, then I will not need to re invent the wheel and be able to use it straight.My application configuration values will be included in that file. I am new to Restlet, I couldn't find any soulution. Any way to do this?
There is no support like this in Restlet. That said you can leverage client protocols to load these properties files from difference locations:
Protocol.FILE - from filesystem directly
Protocol.CLAP - from classpath
Protocol.OBAP - from OSGi bundle
Here is a sample:
ClientResource cr = new ClientResource("clap://someproperties.properties");
Properties props = new Properties();
props.load(cr.get().getStream());
You need to specify this protocol when defining your component:
Component component = new Component();
(...)
component.getServers().add(Protocol.HTTP, 8182);
component.getClients().add(Protocol.CLAP);
So my scenario drilled down to the essence is as follows:
Essentially, I have a config file containing a set of SQL queries whose result sets need to be exported as CSV files.
Since some queries may return billions of rows, and because something may interrupt the process (bug, crash, ...), I want to use a framework such as spring batch, which gives me restartabilty and job monitoring.
I am using a file based H2 database for persisting spring batch jobs.
So, here are my questions:
Upon creating a Job, I need to provide my RowMapper some initial configuration. So what happens when a job needs to be restarted after a e.g. crash? Concretly:
Is the state of the RowMapper automatically persisted, and upon restart Spring batch will try to restore the object from its database, or
will the RowMapper object be used that is part of the original spring batch XML config file, or
I have to maintain the RowMapper's state using the step's/job's ExecutionContext?
Above question is related to whether there is magic going on when using the spring batch XML configuration, or whether I could as well create all these beans in a programmatic way:
Since I need to parse my own config format into a spring batch job config, I rather just use spring batch's Java classes (beans) and fill them out appropriately, rather attempting to manually write out valid XML. However, if my Job crashes, I would create all the beans myself again. Does spring batch automagically restore the Job state from its database?
If I really need XML, is there a way to serialize a spring-batch JobRepository (or one of these objects) as a spring batch XML config?
Right now, I tried to configure my Step with the following code - but I am unsure if this is the proper way to do this:
Is TaskletStep the way to go?
Is the way I create the chunked reader/writer correct, or is there some other object which I should use instead?
I would have assumed that opening of the reader and writer would occur automatically as part of the JobExecution, but if I don't open these resources prior to running the Job, I get an exception telling me that I need to open them first. Maybe I need to create some other object that manages the resoures (jdbc connection and file handle)?
JdbcCursorItemReader<Foobar> itemReader = new JdbcCursorItemReader<Foobar>();
itemReader.setSql(sqlStr);
itemReader.setDataSource(dataSource);
itemReader.setRowMapper(rowMapper);
itemReader.afterPropertiesSet();
ExecutionContext executionContext = new ExecutionContext();
itemReader.open(executionContext);
FlatFileItemWriter<String> itemWriter = new FlatFileItemWriter<String>();
itemWriter.setLineAggregator(new PassThroughLineAggregator<String>());
itemWriter.setResource(outResource);
itemWriter.afterPropertiesSet();
itemWriter.open(executionContext);
int commitInterval = 50000;
CompletionPolicy completionPolicy = new SimpleCompletionPolicy(commitInterval);
RepeatTemplate repeatTemplate = new RepeatTemplate();
repeatTemplate.setCompletionPolicy(completionPolicy);
RepeatOperations repeatOperations = repeatTemplate;
ChunkProvider<Foobar> chunkProvider = new SimpleChunkProvider<Foobar>(itemReader, repeatOperations);
ItemProcessor<Foobar, String> itemProcessor = new ItemProcessor<Foobar, String>() {
/* Custom implemtation */ };
ChunkProcessor<Foobar> chunkProcessor = new SimpleChunkProcessor<Foobar, String>(itemProcessor, itemWriter);
Tasklet tasklet = new ChunkOrientedTasklet<QuadPattern>(chunkProvider, chunkProcessor); //new SplitFilesTasklet();
TaskletStep taskletStep = new TaskletStep();
taskletStep.setName(taskletName);
taskletStep.setJobRepository(jobRepository);
taskletStep.setTransactionManager(transactionManager);
taskletStep.setTasklet(tasklet);
taskletStep.afterPropertiesSet();
job.addStep(taskletStep);
Most of you questions are really complex and can be difficult give a good answer without write a long paper.
I'm new with spring-batch as you, and I found a lot of really useful info - and all the answers to your questions - reading Spring batch in action: it's completed, well explained, full of example and cover all aspects of framework (reader/writer/processor, job/tasklet/chunk lifecycle/persistence, tx/resources management, job flow, integration with other service, partitioning, restarting/retry, failure management and a lot of interesting things).
Hope to help
My problem is every time after changing the Liferay portal-properties (and this is frequent especially at beginning of a new portal project) I need to restart the whole portal.
Some properties I can set over hook and these values will be changed after redeployment. Also that must be possible to change most portal properties at run time.
However, do you know some approach to reflect changes in portal-ext.properties without restarting Liferay portal?
As stoldark mentioned, this is not possible in a production environment at all. Since portal.properties's properties are loaded at portal start-up.
But for development you can use a tool like JRebel, some steps to configure it here. The only issue you would get with this tool is that it is paid ;-).
I know it is a very old thread but it may be helpful for someone who is looking for some type of work around
As we know there is no straight forward way for this but I did this by using java reflection and class loader.
Liferay Version : 6.x
//Loading the PropsUtil class by using PortalClassLoader
Class<?> prospsUtilClass = PortalClassLoaderUtil.getClassLoader().loadClass("com.liferay.portal.util.PropsUtil");
//getting the reload method of PropsUtil class
Method reloadMethod = prospsUtilClass.getMethod("reload", null);
//Invoking the static reload method
reloadMethod.invoke(null, null);
Reload method (re)loads the portal-ext properties to the portal so we can use new properties without restarting Liferay server.
This has also been asked in Liferay forums:
https://www.liferay.com/community/forums/-/message_boards/message/800954
But I am afraid that most properties are only read once during portal startup.
Usually, the use of a properties file as in this case has this drawback.
There's even an issue open at Liferay about this, but is still unresolved:
http://issues.liferay.com/browse/LEP-5579
If you create a hook to override portal properties, you will be able to change properties with just deploying the hook without restarting the Portal.
Be aware that you cannot modify all properties with a hook. For a list of the ones that you can modify, check out: https://docs.liferay.com/portal/6.2/definitions/.
I've just searched for reloading portal-ext.properties and landed here.
Ok - not a feature in Liferay.
So I'll use an old trick I like:
place custom properties in (liferay-tomcat-home)/conf/filename.properties
reload them whenever you want by
Properties customProperties = new Properties();
customProperties.load(new FileInputStream(new File(System.getProperty("catalina.base"), "conf/filename.properties")));
I must confess I haven't tried this in a Liferay-Portlet-Environment, but this system property ("catalina.base") should be available in this context, at least by using some Liferay-Helper-Class.
Some of the Liferay classes read their properties when initialising static field constants. E.g.:
public static final boolean ENABLED = GetterUtil.getBoolean(
PropsUtil.get(DynamicCSSFilter.class.getName()));
Basically, it is possible to reload the properties (eg via script in control-panel), but all those static constants will remain.