Make package private classes final.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/csv/trunk@1397907 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/csv/CSVLexer.java

@@ -25,7 +25,7 @@ import static org.apache.commons.csv.Token.Type.TOKEN;
 
 import java.io.IOException;
 
-class CSVLexer extends Lexer {
+final class CSVLexer extends Lexer {
 
     /** ctor needs to be public so can be called dynamically by PerformanceTest class */
     public CSVLexer(final CSVFormat format, final ExtendedBufferedReader in) {

src/main/java/org/apache/commons/csv/Constants.java

@@ -20,7 +20,7 @@ package org.apache.commons.csv;
 /**
  * Constants for this package.
  */
-class Constants {
+final class Constants {
     
     static final char BACKSPACE = '\b';
     static final char COMMA = ',';

src/main/java/org/apache/commons/csv/ExtendedBufferedReader.java

@@ -32,7 +32,7 @@ import java.io.Reader;
  * In particular the reader supports a look-ahead option, which allows you to see the next char returned by
  * {@link #read()}.
  */
-class ExtendedBufferedReader extends BufferedReader {
+final class ExtendedBufferedReader extends BufferedReader {
 
     /** The last char returned */
     private int lastChar = UNDEFINED;

src/main/java/org/apache/commons/csv/Token.java

@@ -24,7 +24,7 @@ import static org.apache.commons.csv.Token.Type.INVALID;
  * <p/>
  * It is used as contract between the lexer and the parser.
  */
-class Token {
+final class Token {
 
     /** length of the initial token (content-)buffer */
     private static final int INITIAL_TOKEN_LENGTH = 50;