Available in Community Designer

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.

Create a component being able to write all input metadata fields as strings. Input metadata fields can include maps and lists.

Solution

package jk;

import java.io.IOException;
import java.io.OutputStream;

import org.jetel.component.AbstractGenericTransform;
import org.jetel.data.DataField;
import org.jetel.data.DataRecord;
import org.jetel.exception.JetelRuntimeException;

/**
 * This is an example custom writer. It shows how you can write string 
 * representations of fields into file.
 */
public class CustomJavaWriterExample01 extends AbstractGenericTransform {
	@Override
	public void execute() {
		String fileUrl = getProperties().getStringProperty("FileUrl");
		DataRecord record;

		try (OutputStream os = getOutputStream(fileUrl, false)) {
			while ((record = readRecordFromPort(0)) != null) {
				StringBuffer sb = new StringBuffer();
				DataField[] dataFields = record.getFields();

				int fieldCount = 1;
				for (DataField df : dataFields) {
					sb.append(df.getValue() != null ? df.getValue().toString() : "");
					if (df.getMetadata().getDelimiter() != null) {
						sb.append(df.getMetadata().getDelimiter());
					} else {
						if (fieldCount != dataFields.length) {
							sb.append(record.getMetadata().getFieldDelimiter());
						}
					}
					++fieldCount;
				}
				sb.append(record.getMetadata().getRecordDelimiter());
				os.write(sb.toString().getBytes("UTF-8"));
			}
		} catch (IOException e) {
			throw new JetelRuntimeException(e);
		}
	}
}