Method convert

src/java/simpledb/index/BTreeFileEncoder.java:34–57

Encode the file using the BTreeFile's Insert method. @param tuples - list of tuples to add to the file @param hFile - the file to temporarily store the data as a heap file on disk @param bFile - the file on disk to back the resulting BTreeFile @param keyField - the index of the key field for this B

(List<List<Integer>> tuples, File hFile,
			File bFile, int keyField, int numFields)

	 * @return the BTreeFile
	 */
	public static BTreeFile convert(List<List<Integer>> tuples, File hFile,
			File bFile, int keyField, int numFields) throws IOException {
		File tempInput = File.createTempFile("tempTable", ".txt");
		tempInput.deleteOnExit();
		BufferedWriter bw = new BufferedWriter(new FileWriter(tempInput));
		for (List<Integer> tuple : tuples) {
			int writtenFields = 0;
			for (Integer field : tuple) {
				writtenFields++;
				if (writtenFields > numFields) {
					bw.close();
					throw new RuntimeException("Tuple has more than " + numFields + " fields: (" +
							Utility.listToString(tuple) + ")");
				}
				bw.write(String.valueOf(field));
				if (writtenFields < numFields) {
					bw.write(',');
				}
			}
			bw.write('\n');
		}
		bw.close();
		return convert(tempInput, hFile, bFile, keyField, numFields);
	}

	/**
	 * Encode the file using the BTreeFile's Insert method.