Defines a compilation unit. In Java, a compilation unit can contain only one
public type declaration and other secondary types declarations (not public).
Helper method to get the begin index of the line that corresponds to the
given index.
Parameters: index - an arbitrary index in the source code the index where the line starts
Gets the number of tabulations for a given line.
Parameters: index - the index where the line starts in the source code the number of tabs for this line
Helper method to get the begin index of the line that corresponds to the
next line of the given index.
Parameters: index - an arbitrary index in the source code the index where the next line starts