How to renames the slide master - apache-poi

Question

I want rename the PowerPoint slide master by apache poi. In PowerPoint GUI we do View - Slide Master - then we right click the top most slide on left side and select Rename Master from context menu.

Answer 1

In a PowerPoint presentation the master is named such as it's theme. We can get all masters using XMLSlideShow.getSlideMasters. XSLFSlideMaster
extends XSLFSheet. So we can get the theme of each master using XSLFSheet.getTheme. Once we have the XSLFTheme there are getters and setters for the name.
Example:
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.poi.xslf.usermodel.*;
public class XSLFRenameMasterTheme {
public static void main(String[] args) throws Exception {
XMLSlideShow slideshow = new XMLSlideShow(new FileInputStream("Presentation.pptx"));
for (XSLFSlideMaster master : slideshow.getSlideMasters()) {
XSLFTheme theme = master.getTheme();
String name = theme.getName();
System.out.println(name);
theme.setName(name + " renamed");
System.out.println(theme.getName());
}
FileOutputStream out = new FileOutputStream("PresentationRenamedMaster.pptx");
slideshow.write(out);
out.close();
slideshow.close();
}
}
For HSLFSlideShow is seems there is no access to master names supported. One can get the HSLFSlideMasters but not the names of them.
So if one needs doing that nevertheless, then one must know about the internals of the binary *.ppt file system. This is documented in [MS-PPT]: PowerPoint (.ppt) Binary File Format. The sheet names are in a SlideNameAtom. With knowledge about the internals one can create a class for that kind of record. This can providing methods for get and set the name then.
Example:
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.ByteArrayOutputStream;
import org.apache.poi.hslf.usermodel.*;
import org.apache.poi.hslf.record.Record;
import org.apache.poi.hslf.record.RecordAtom;
import org.apache.poi.util.LittleEndian;
import org.apache.poi.util.StringUtil;
public class HSLFRenameMaster {
// method for get SlideNameAtom out of the master
private static SlideNameAtom getSlideNameAtom(HSLFSlideMaster master) throws Exception {
SlideNameAtom slideNameAtomRecord = null;
Record record = master.getSheetContainer().findFirstOfType(0x0FBA);
if (record != null) { // SlideNameAtom exists
// get present data
ByteArrayOutputStream out = new ByteArrayOutputStream();
record.writeOut(out);
out.flush();
byte[] data = out.toByteArray();
out.close();
// create new SlideNameAtom from data
slideNameAtomRecord = new SlideNameAtom(data);
// replace old record with new SlideNameAtom
master.getSheetContainer().addChildBefore(
slideNameAtomRecord,
record
);
master.getSheetContainer().removeChild(record);
}
return slideNameAtomRecord;
}
public static void main(String[] args) throws Exception {
HSLFSlideShow slideshow = new HSLFSlideShow(new FileInputStream("Presentation.ppt"));
for (HSLFSlideMaster master : slideshow.getSlideMasters()) {
SlideNameAtom slideNameAtomRecord = getSlideNameAtom(master);
if (slideNameAtomRecord != null) {
String name = slideNameAtomRecord.getName();
System.out.println(name);
slideNameAtomRecord.setName(name + " renamed");
System.out.println(slideNameAtomRecord.getName());
}
}
FileOutputStream out = new FileOutputStream("PresentationRenamedMaster.ppt");
slideshow.write(out);
out.close();
slideshow.close();
}
//class SlideNameAtom
//having methods for manipulating the [SlideNameAtom](https://msdn.microsoft.com/en-us/library/dd906297(v=office.12).aspx)
private static class SlideNameAtom extends RecordAtom {
private byte[] data;
private String name;
public SlideNameAtom() {
this.name = "Office";
setName(name);
}
public SlideNameAtom(byte[] data) {
this.data = data;
this.name = getName();
}
public void setName(String name) {
this.name = name;
int length = 8;
length += StringUtil.getToUnicodeLE(name).length;
this.data = new byte[length];
data[0] = (byte)0x20; data[1] = (byte)0x00;
data[2] = (byte)0xBA; data[3] = (byte)0x0F; //MUST be 0x0fba = RT_CString (little endian)
LittleEndian.putInt(data, 4, StringUtil.getToUnicodeLE(name).length);
StringUtil.putUnicodeLE(name, data, 8);
}
public String getName() {
return StringUtil.getFromUnicodeLE(this.data, 8, (this.data.length-8)/2);
}
#Override
public void writeOut(OutputStream out) throws IOException {
out.write(data);
}
#Override
public long getRecordType() { return 0x0FBA; }
}
}
The question is whether renaming the master is worth that effort.