CustomJavaTransformer
Available in Community Designer
| Short Description |
| Ports |
| Metadata |
| CustomJavaTransformer Attributes |
| Details |
| Examples |
| Best Practices |
| Compatibility |
| See also |
Short Description
CustomJavaTransformer executes user-defined Java code.
| Component | Same input metadata | Sorted inputs | Inputs | Outputs | Each to all outputs | Java | CTL | Auto-propagated metadata |
|---|---|---|---|---|---|---|---|---|
| CustomJavaTransformer | - | - | 0-n | 0-n | - |  |  | |
Icon
Ports
Number of ports depends on the java code.
Metadata
CustomJavaTransformer does not propagate metadata.
CustomJavaTransformer has no metadata templates.
Requirements on metadata depend on user-defined transformation.
CustomJavaTransformer Attributes
| Attribute | Req | Description | Possible values |
|---|---|---|---|
| Basic | |||
| Algorithm | [1] | Runnable transformation in Java defined in the graph. | |
| Algorithm URL | [1] | External file defining the runnable transformation in Java. | |
| Algorithm class | [1] | External runnable transformation class. | |
| Algorithm source charset |
Encoding of external file defining the transformation. The default encoding depends on DEFAULT_SOURCE_CODE_CHARSET in defaultProperties. | E.g. UTF-8 | |
[1] One of these must be set. These transformation attributes must be specified. | |||
Details
CustomJavaTransformer executes Java transformation. CustomJavaTransformer is a more specific CustomJavaComponent and it is focused on transforming data.
There are other similar java components: CustomJavaReader, CustomJavaWriter and CustomJavaComponent. All these components use transformation defined in java, they differ in templates being used.
You can use Public Clover API in this component. Documentation on general parts of custom java components and Public Clover API is described in CustomJavaComponent.
Java Interfaces for CustomJavaComponent
Transformation required by the component must extend org.jetel.component.AbstractGenericTransform class.
The component has same java interface as CustomJavaComponent, but it provides different java template. See Java Interfaces for CustomJavaComponent.
Examples
Record Duplicator
Create a component duplicating input records.
Solution
package jk;
import org.jetel.component.AbstractGenericTransform;
import org.jetel.data.DataRecord;
import org.jetel.exception.JetelRuntimeException;
/**
* This is an example custom transformer. It shows how you can
* duplicate all incoming records.
*/
public class CustomJavaTransformerExample01 extends AbstractGenericTransform {
@Override
public void execute() {
try {
DataRecord inRecord = inRecords[0];
while ((inRecord = readRecordFromPort(0)) != null) {
writeRecordToPort(0, inRecord);
writeRecordToPort(0, inRecord);
}
} catch (Exception e) {
throw new JetelRuntimeException(e);
}
}
}Metadata on input and output port must be the same for this example.
Best Practices
If the transformation is specified in an external file (with Algorithm URL), we recommend users to explicitly specify Algorithm source charset.
Compatibility
CustomJavaTransformer is available since CloverETL 4.1.0-M1. It replaced JavaExecute.