JDBC Data Adapter [Java]

[giuseppe.corti]

Certainly, since you have added parameters in the `<data_provider>` section, you will need to add code to read and use them. Therefore, in the `init` method of your Data Adapter, you will need to implement something similar to the following:

```java
public void init(Map params, File configDir) throws DataProviderException {
// Read the DB parameters
String db_host = (String) params.get("db_hostname");
String db_user = (String) params.get("db_user");
...

}
```

Once you have retrieved the configuration parameters, you can utilize them within the `init` method or store them as instance variables to be used in other methods of your Data Adapter.

Sorry but I am not sure what do you mean for "output in the Lightstreamer", if you refer to the log messages generated by Lightstreamer, including the logs related to the loading of adapters and client requests. You can find these logs in the <LS_HOME>/logs directory.
If you are looking for a web application that acts as a client for this adapter, you can refer to this project:

[Project Name: Lightstreamer - "Hello World" Tutorial - HTML Client]
[GitHub Repository: https://github.com/Lightstreamer/Lig...ent-javascript]

This web application can serve as a client for your adapter and provide an interface for the visualization of the data provided by the adapter. You can find more details and the necessary code in the provided GitHub repository.

Reagrds,
Giuseppe

[vinayak singh]

Hi Giuseppe,

I am encountering an error while trying to run this code in the IntelliJ. The error is

No com.lightstreamer.kernel_lib_path defined; using a unique ClassLoader; ignoring any other _lib_path supplied
Unexpected error in initialization phase:

How to solve this error? I am using a windows system. Please help me regarding this issue, This is my adapters.xml file

<?xml version="1.0" encoding="UTF-8"?>


<!-- Do not remove this line. File tag: adapters_conf-APV-7.2.0. -->


<!-- This is a generic template for the configuration file of an Adapter Set pluggable into Lightstreamer Server. It can be considered a reference example of an in-process Java Adapter deploy. Note that element and attribute names are case-sensitive.
A very simple variable-expansion feature is available; see <enable_expansion_for_adapters_config> in the Server's main configuration file. -->


<!-- Mandatory. Define an Adapter Set and its unique ID. -->
<adapters_conf id="HELLOWORLD">


<metadata_provider>


<!-- Mandatory. Java class name of the adapter. -->
<adapter_class>classfile.adapters.metadata.Literal BasedProvider</adapter_class>


</metadata_provider>


<!-- Mandatory. Define a Data Adapter named "HelloWorldAdapter". -->
<data_provider name="HelloWorldDataAdapter">

<param name="db_hostname">localhost</param>
<param name="db_user">root</param>
<param name="db_password">xxxx</param>
<param name="jdbc_driver">com.mysql.jdbc.Driver</param>
<adapter_class>classfile.adapters.HelloWorldDataAd apter</adapter_class>
</data_provider>


</adapters_conf>