org.apache.poi.POITextExtractor Maven / Gradle / Ivy
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package org.apache.poi;
import java.io.Closeable;
import java.io.IOException;
/**
* Common Parent for Text Extractors
* of POI Documents.
* You will typically find the implementation of
* a given format's text extractor under
* org.apache.poi.[format].extractor .
* @see org.apache.poi.hssf.extractor.ExcelExtractor
* @see org.apache.poi.hslf.extractor.PowerPointExtractor
* @see org.apache.poi.hdgf.extractor.VisioTextExtractor
* @see org.apache.poi.hwpf.extractor.WordExtractor
*/
public abstract class POITextExtractor implements Closeable {
/** The POIDocument that's open */
protected POIDocument document;
/**
* Creates a new text extractor for the given document
*/
public POITextExtractor(POIDocument document) {
this.document = document;
}
/**
* Creates a new text extractor, using the same
* document as another text extractor. Normally
* only used by properties extractors.
*/
protected POITextExtractor(POITextExtractor otherExtractor) {
this.document = otherExtractor.document;
}
/**
* Retrieves all the text from the document.
* How cells, paragraphs etc are separated in the text
* is implementation specific - see the javadocs for
* a specific project for details.
* @return All the text from the document
*/
public abstract String getText();
/**
* Returns another text extractor, which is able to
* output the textual content of the document
* metadata / properties, such as author and title.
*/
public abstract POITextExtractor getMetadataTextExtractor();
/**
* Allows to free resources of the Extractor as soon as
* it is not needed any more. This may include closing
* open file handles and freeing memory.
*
* The Extractor cannot be used after close has been called.
*/
public void close() throws IOException {
// nothing to do in abstract class, derived classes may perform actions.
}
}