/** Parses a {@code LineNumberTable} attribute. */
private Attribute lineNumberTable(
DirectClassFile cf, int offset, int length, ParseObserver observer) {
if (length < 2) {
return throwSeverelyTruncated();
}
ByteArray bytes = cf.getBytes();
int count = bytes.getUnsignedShort(offset); // line_number_table_length
if (observer != null) {
observer.parsed(bytes, offset, 2, "line_number_table_length: " + Hex.u2(count));
}
offset += 2;
length -= 2;
if (length != (count * 4)) {
throwBadLength((count * 4) + 2);
}
LineNumberList list = new LineNumberList(count);
for (int i = 0; i < count; i++) {
int startPc = bytes.getUnsignedShort(offset);
int lineNumber = bytes.getUnsignedShort(offset + 2);
list.set(i, startPc, lineNumber);
if (observer != null) {
observer.parsed(bytes, offset, 4, Hex.u2(startPc) + " " + lineNumber);
}
offset += 4;
}
list.setImmutable();
return new AttLineNumberTable(list);
}