com.Ostermiller.util.CSVLexer Maven / Gradle / Ivy
/* The following code was generated by JFlex 1.4.1 on 21/01/08 9.43 */
/* CSVLexer.java is a generated file. You probably want to
* edit CSVLexer.lex to make changes. Use JFlex to generate it.
* JFlex may be obtained from
* the JFlex website.
* This file was tested to work with jflex 1.4 (and may not
* work with more recent version because it needs a skeleton file)
* Run:
* jflex --skel csv.jflex.skel CSVLexer.lex
* You will then have a file called CSVLexer.java
*/
/*
* Read files in comma separated value format.
* Copyright (C) 2001-2004 Stephen Ostermiller
* http://ostermiller.org/contact.pl?regarding=Java+Utilities
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* See COPYING.TXT for details.
*/
package com.Ostermiller.util;
import java.io.*;
/**
* Read files in comma separated value format.
*
* The use of this class is no longer recommended. It is now recommended that you use
* com.Ostermiller.util.CSVParser instead. That class, has a cleaner API, and methods
* for returning all the values on a line in a String array.
*
* CSV is a file format used as a portable representation of a database.
* Each line is one entry or record and the fields in a record are separated by commas.
* Commas may be preceded or followed by arbitrary space and/or tab characters which are
* ignored.
*
* If field includes a comma or a new line, the whole field must be surrounded with double quotes.
* When the field is in quotes, any quote literals must be escaped by \" Backslash
* literals must be escaped by \\. Otherwise a backslash an the character following it
* will be treated as the following character, ie."\n" is equivelent to "n". Other escape
* sequences may be set using the setEscapes() method. Text that comes after quotes that have
* been closed but come before the next comma will be ignored.
*
* Empty fields are returned as as String of length zero: "". The following line has four empty
* fields and two non-empty fields in it. There is an empty field on each end, and two in the
* middle.
*
,second,, ,fifth,
*
* Blank lines are always ignored. Other lines will be ignored if they start with a
* comment character as set by the setCommentStart() method.
*
* An example of how CVSLexer might be used:
*
* CSVLexer shredder = new CSVLexer(System.in);
* shredder.setCommentStart("#;!");
* shredder.setEscapes("nrtf", "\n\r\t\f");
* String t;
* while ((t = shredder.getNextToken()) != null) {
* System.out.println("" + shredder.getLineNumber() + " " + t);
* }
*
*
* @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
* @since ostermillerutils 1.00.00
*/
public class CSVLexer {
/** This character denotes the end of file */
public static final int YYEOF = -1;
/** initial size of the lookahead buffer */
private static final int ZZ_BUFFERSIZE = 16384;
/** lexical states */
public static final int BEFORE = 1;
public static final int YYINITIAL = 0;
public static final int COMMENT = 3;
public static final int AFTER = 2;
/**
* Translates characters to character classes
*/
private static final String ZZ_CMAP_PACKED =
"\11\0\1\1\1\3\1\0\1\1\1\2\22\0\1\1\1\0\1\5"+
"\11\0\1\4\57\0\1\6\uffa3\0";
/**
* Translates characters to character classes
*/
private static final char [] ZZ_CMAP = zzUnpackCMap(ZZ_CMAP_PACKED);
/**
* Translates DFA states to action switch labels.
*/
private static final int [] ZZ_ACTION = zzUnpackAction();
private static final String ZZ_ACTION_PACKED_0 =
"\1\0\3\1\1\2\1\3\2\4\1\5\1\6\1\7"+
"\1\1\2\10\1\11\1\12\2\1\1\13\1\1\2\0"+
"\1\14\2\0\1\15\1\0";
private static int [] zzUnpackAction() {
int [] result = new int[27];
int offset = 0;
offset = zzUnpackAction(ZZ_ACTION_PACKED_0, offset, result);
return result;
}
private static int zzUnpackAction(String packed, int offset, int [] result) {
int i = 0; /* index in packed string */
int j = offset; /* index in unpacked array */
int l = packed.length();
while (i < l) {
int count = packed.charAt(i++);
int value = packed.charAt(i++);
do result[j++] = value; while (--count > 0);
}
return j;
}
/**
* Translates a state to a row index in the transition table
*/
private static final int [] ZZ_ROWMAP = zzUnpackRowMap();
private static final String ZZ_ROWMAP_PACKED_0 =
"\0\0\0\7\0\16\0\25\0\34\0\43\0\52\0\61"+
"\0\61\0\70\0\77\0\106\0\115\0\61\0\61\0\124"+
"\0\133\0\142\0\61\0\151\0\34\0\43\0\61\0\160"+
"\0\77\0\61\0\167";
private static int [] zzUnpackRowMap() {
int [] result = new int[27];
int offset = 0;
offset = zzUnpackRowMap(ZZ_ROWMAP_PACKED_0, offset, result);
return result;
}
private static int zzUnpackRowMap(String packed, int offset, int [] result) {
int i = 0; /* index in packed string */
int j = offset; /* index in unpacked array */
int l = packed.length();
while (i < l) {
int high = packed.charAt(i++) << 16;
result[j++] = high | packed.charAt(i++);
}
return j;
}
/**
* The transition table of the DFA
*/
private static final int [] ZZ_TRANS = zzUnpackTrans();
private static final String ZZ_TRANS_PACKED_0 =
"\1\5\1\6\1\7\1\10\1\11\1\12\1\5\1\13"+
"\1\14\1\15\1\16\1\17\1\20\1\13\1\21\1\22"+
"\1\7\1\10\1\23\2\21\1\24\1\4\1\7\1\10"+
"\3\24\1\5\1\25\3\0\2\5\1\0\1\26\1\7"+
"\1\10\6\0\1\10\12\0\5\12\1\27\1\30\1\13"+
"\1\31\3\0\2\13\1\0\1\14\10\0\1\16\3\0"+
"\5\20\1\32\1\33\2\21\3\0\3\21\1\22\1\7"+
"\1\10\1\0\2\21\2\24\2\0\3\24\7\12\7\20";
private static int [] zzUnpackTrans() {
int [] result = new int[126];
int offset = 0;
offset = zzUnpackTrans(ZZ_TRANS_PACKED_0, offset, result);
return result;
}
private static int zzUnpackTrans(String packed, int offset, int [] result) {
int i = 0; /* index in packed string */
int j = offset; /* index in unpacked array */
int l = packed.length();
while (i < l) {
int count = packed.charAt(i++);
int value = packed.charAt(i++);
value--;
do result[j++] = value; while (--count > 0);
}
return j;
}
/**
* Per instance reference to the character map.
* This can be cloned and modified per instance if needed.
* It is initally set to the static value.
*/
private char [] zzcmap_instance = ZZ_CMAP;
/* error codes */
private static final int ZZ_UNKNOWN_ERROR = 0;
private static final int ZZ_NO_MATCH = 1;
private static final int ZZ_PUSHBACK_2BIG = 2;
/* error messages for the codes above */
private static final String ZZ_ERROR_MSG[] = {
"Unkown internal scanner error",
"Error: could not match input",
"Error: pushback value was too large"
};
/**
* ZZ_ATTRIBUTE[aState] contains the attributes of state aState
*/
private static final int [] ZZ_ATTRIBUTE = zzUnpackAttribute();
private static final String ZZ_ATTRIBUTE_PACKED_0 =
"\1\0\6\1\2\11\4\1\2\11\3\1\1\11\1\1"+
"\2\0\1\11\2\0\1\11\1\0";
private static int [] zzUnpackAttribute() {
int [] result = new int[27];
int offset = 0;
offset = zzUnpackAttribute(ZZ_ATTRIBUTE_PACKED_0, offset, result);
return result;
}
private static int zzUnpackAttribute(String packed, int offset, int [] result) {
int i = 0; /* index in packed string */
int j = offset; /* index in unpacked array */
int l = packed.length();
while (i < l) {
int count = packed.charAt(i++);
int value = packed.charAt(i++);
do result[j++] = value; while (--count > 0);
}
return j;
}
/** the input device */
private java.io.Reader zzReader;
/** the current state of the DFA */
private int zzState;
/** the current lexical state */
private int zzLexicalState = YYINITIAL;
/** this buffer contains the current text to be matched and is
the source of the yytext() string */
private char zzBuffer[] = new char[ZZ_BUFFERSIZE];
/** the textposition at the last accepting state */
private int zzMarkedPos;
/** the textposition at the last state to be included in yytext */
private int zzPushbackPos;
/** the current text position in the buffer */
private int zzCurrentPos;
/** startRead marks the beginning of the yytext() string in the buffer */
private int zzStartRead;
/** endRead marks the last character in the buffer, that has been read
from input */
private int zzEndRead;
/** number of newlines encountered up to the start of the matched text */
private int yyline;
/** the number of characters up to the start of the matched text */
private int yychar;
/**
* the number of characters from the last newline up to the start of the
* matched text
*/
private int yycolumn;
/**
* zzAtBOL == true <=> the scanner is currently at the beginning of a line
*/
private boolean zzAtBOL = true;
/** zzAtEOF == true <=> the scanner is at the EOF */
private boolean zzAtEOF;
/* user code: */
/**
* Prints out tokens and line numbers from a file or System.in.
* If no arguments are given, System.in will be used for input.
* If more arguments are given, the first argument will be used as
* the name of the file to use as input
*
* @param args program arguments, of which the first is a filename
*
* @since ostermillerutils 1.00.00
*/
public static void main(String[] args){
InputStream in;
try {
if (args.length > 0){
File f = new File(args[0]);
if (f.exists()){
if (f.canRead()){
in = new FileInputStream(f);
} else {
throw new IOException("Could not open " + args[0]);
}
} else {
throw new IOException("Could not find " + args[0]);
}
} else {
in = System.in;
}
CSVLexer shredder = new CSVLexer(in);
shredder.setCommentStart("#;!");
shredder.setEscapes("nrtf", "\n\r\t\f");
String t;
while ((t = shredder.getNextToken()) != null) {
System.out.println("" + shredder.getLineNumber() + " " + t);
}
} catch (IOException e){
System.out.println(e.getMessage());
}
}
private char delimiter = ',';
private char quote = '\"';
/**
* Checks that zzcmap_instance is an instance variable (not just
* a pointer to a static variable). If it is a pointer to a static
* variable, it will be cloned.
*
* @since ostermillerutils 1.00.00
*/
private void ensureCharacterMapIsInstance(){
if (ZZ_CMAP == zzcmap_instance){
zzcmap_instance = new char[ZZ_CMAP.length];
System.arraycopy(ZZ_CMAP, 0, zzcmap_instance, 0, ZZ_CMAP.length);
}
}
/**
* Ensures that the given character is not used for some special purpose
* in parsing. This method should be called before setting some character
* to be a delimiter so that the parsing doesn't break. Examples of bad
* characters are quotes, commas, and whitespace.
*
* @since ostermillerutils 1.00.00
*/
private boolean charIsSafe(char c){
// There are two character classes that one could use as a delimiter.
// The first would be the class that most characters are in. These
// are normally data. The second is the class that the tab is usually in.
return (zzcmap_instance[c] == ZZ_CMAP['a'] || zzcmap_instance[c] == ZZ_CMAP['\t']);
}
/**
* Change the character classes of the two given characters. This
* will make the state machine behave as if the characters were switched
* when they are encountered in the input.
*
* @param old the old character, its value will be returned to initial
* @param two second character
*
* @since ostermillerutils 1.00.00
*/
private void updateCharacterClasses(char oldChar, char newChar){
// before modifying the character map, make sure it isn't static.
ensureCharacterMapIsInstance();
// make the newChar behave like the oldChar
zzcmap_instance[newChar] = zzcmap_instance[oldChar];
// make the oldChar behave like it isn't special.
switch (oldChar){
case ',':
case '"': {
// These should act as normal character,
// not delimiters or quotes right now.
zzcmap_instance[oldChar] = ZZ_CMAP['a'];
} break;
default: {
// Set the it back to the way it would act
// if not used as a delimiter or quote.
zzcmap_instance[oldChar] = ZZ_CMAP[oldChar];
} break;
}
}
/**
* Change this Lexer so that it uses a new delimiter.
*
* The initial character is a comma, the delimiter cannot be changed
* to a quote or other character that has special meaning in CSV.
*
* @param newDelim delimiter to which to switch.
* @throws BadDelimiterException if the character cannot be used as a delimiter.
*
* @since ostermillerutils 1.00.00
*/
public void changeDelimiter(char newDelim) throws BadDelimiterException {
if (newDelim == delimiter) return; // no need to do anything.
if (!charIsSafe(newDelim)){
throw new BadDelimiterException(newDelim + " is not a safe delimiter.");
}
updateCharacterClasses(delimiter, newDelim);
// keep a record of the current delimiter.
delimiter = newDelim;
}
/**
* Change this Lexer so that it uses a new character for quoting.
*
* The initial character is a double quote ("), the delimiter cannot be changed
* to a comma or other character that has special meaning in CSV.
*
* @param newQuote character to use for quoting.
* @throws BadQuoteException if the character cannot be used as a quote.
*
* @since ostermillerutils 1.00.00
*/
public void changeQuote(char newQuote) throws BadQuoteException {
if (newQuote == quote) return; // no need to do anything.
if (!charIsSafe(newQuote)){
throw new BadQuoteException(newQuote + " is not a safe quote.");
}
updateCharacterClasses(quote, newQuote);
// keep a record of the current quote.
quote = newQuote;
}
private String escapes = "";
private String replacements = "";
/**
* Specify escape sequences and their replacements.
* Escape sequences set here are in addition to \\ and \".
* \\ and \" are always valid escape sequences. This method
* allows standard escape sequenced to be used. For example
* "\n" can be set to be a newline rather than an 'n'.
* A common way to call this method might be:
* setEscapes("nrtf", "\n\r\t\f");
* which would set the escape sequences to be the Java escape
* sequences. Characters that follow a \ that are not escape
* sequences will still be interpreted as that character.
* The two arguemnts to this method must be the same length. If
* they are not, the longer of the two will be truncated.
*
* @param escapes a list of characters that will represent escape sequences.
* @param replacements the list of repacement characters for those escape sequences.
*
* @since ostermillerutils 1.00.00
*/
public void setEscapes(String escapes, String replacements){
int length = escapes.length();
if (replacements.length() < length){
length = replacements.length();
}
this.escapes = escapes.substring(0, length);
this.replacements = replacements.substring(0, length);
}
private String unescape(String s){
if (s.indexOf('\\') == -1){
return s.substring(1, s.length()-1);
}
StringBuffer sb = new StringBuffer(s.length());
for (int i=1; i
* # Comment
* ; Another Comment
* ! Yet another comment
* By default there are no comments in CVS files. Commas and quotes may not be
* used to indicate comment lines.
*
* @param commentDelims list of characters a comment line may start with.
*
* @since ostermillerutils 1.00.00
*/
public void setCommentStart(String commentDelims){
this.commentDelims = commentDelims;
}
private int addLine = 1;
private int lines = 0;
/**
* Get the line number that the last token came from.
*
* New line breaks that occur in the middle of a token are not
* counted in the line number count.
*
* If no tokens have been returned, the line number is undefined.
*
* @return line number of the last token.
*
* @since ostermillerutils 1.00.00
*/
public int getLineNumber(){
return lines;
}
/**
* Creates a new scanner
* There is also a java.io.InputStream version of this constructor.
*
* @param in the java.io.Reader to read input from.
*/
public CSVLexer(java.io.Reader in) {
this.zzReader = in;
}
/**
* Creates a new scanner.
* There is also java.io.Reader version of this constructor.
*
* @param in the java.io.Inputstream to read input from.
*/
public CSVLexer(java.io.InputStream in) {
this(new java.io.InputStreamReader(in));
}
/**
* Unpacks the compressed character translation table.
*
* @param packed the packed character translation table
* @return the unpacked character translation table
*/
private static char [] zzUnpackCMap(String packed) {
char [] map = new char[0x10000];
int i = 0; /* index in packed string */
int j = 0; /* index in unpacked array */
while (i < 30) {
int count = packed.charAt(i++);
char value = packed.charAt(i++);
do map[j++] = value; while (--count > 0);
}
return map;
}
/**
* Refills the input buffer.
*
* @return false, iff there was new input.
*
* @exception java.io.IOException if any I/O-Error occurs
*/
private boolean zzRefill() throws java.io.IOException {
/* first: make room (if you can) */
if (zzStartRead > 0) {
System.arraycopy(zzBuffer, zzStartRead,
zzBuffer, 0,
zzEndRead-zzStartRead);
/* translate stored positions */
zzEndRead-= zzStartRead;
zzCurrentPos-= zzStartRead;
zzMarkedPos-= zzStartRead;
zzPushbackPos-= zzStartRead;
zzStartRead = 0;
}
/* is the buffer big enough? */
if (zzCurrentPos >= zzBuffer.length) {
/* if not: blow it up */
char newBuffer[] = new char[zzCurrentPos*2];
System.arraycopy(zzBuffer, 0, newBuffer, 0, zzBuffer.length);
zzBuffer = newBuffer;
}
/* finally: fill the buffer with new input */
int numRead = zzReader.read(zzBuffer, zzEndRead,
zzBuffer.length-zzEndRead);
if (numRead < 0) {
return true;
}
else {
zzEndRead+= numRead;
return false;
}
}
/**
* Closes the input stream.
*/
public final void yyclose() throws java.io.IOException {
zzAtEOF = true; /* indicate end of file */
zzEndRead = zzStartRead; /* invalidate buffer */
if (zzReader != null)
zzReader.close();
}
/**
* Resets the scanner to read from a new input stream.
* Does not close the old reader.
*
* All internal variables are reset, the old input stream
* cannot be reused (internal buffer is discarded and lost).
* Lexical state is set to ZZ_INITIAL.
*
* @param reader the new input stream
*/
public final void yyreset(java.io.Reader reader) {
zzReader = reader;
zzAtBOL = true;
zzAtEOF = false;
zzEndRead = zzStartRead = 0;
zzCurrentPos = zzMarkedPos = zzPushbackPos = 0;
yyline = yychar = yycolumn = 0;
zzLexicalState = YYINITIAL;
}
/**
* Returns the current lexical state.
*/
public final int yystate() {
return zzLexicalState;
}
/**
* Enters a new lexical state
*
* @param newState the new lexical state
*/
public final void yybegin(int newState) {
zzLexicalState = newState;
}
/**
* Returns the text matched by the current regular expression.
*/
public final String yytext() {
return new String( zzBuffer, zzStartRead, zzMarkedPos-zzStartRead );
}
/**
* Returns the character at position pos from the
* matched text.
*
* It is equivalent to yytext().charAt(pos), but faster
*
* @param pos the position of the character to fetch.
* A value from 0 to yylength()-1.
*
* @return the character at position pos
*/
public final char yycharat(int pos) {
return zzBuffer[zzStartRead+pos];
}
/**
* Returns the length of the matched text region.
*/
public final int yylength() {
return zzMarkedPos-zzStartRead;
}
/**
* Reports an error that occured while scanning.
*
* In a wellformed scanner (no or only correct usage of
* yypushback(int) and a match-all fallback rule) this method
* will only be called with things that "Can't Possibly Happen".
* If this method is called, something is seriously wrong
* (e.g. a JFlex bug producing a faulty scanner etc.).
*
* Usual syntax/scanner level error handling should be done
* in error fallback rules.
*
* @param errorCode the code of the errormessage to display
*/
private void zzScanError(int errorCode) {
String message;
try {
message = ZZ_ERROR_MSG[errorCode];
}
catch (ArrayIndexOutOfBoundsException e) {
message = ZZ_ERROR_MSG[ZZ_UNKNOWN_ERROR];
}
throw new Error(message);
}
/**
* Pushes the specified amount of characters back into the input stream.
*
* They will be read again by then next call of the scanning method
*
* @param number the number of characters to be read again.
* This number must not be greater than yylength()!
*/
public void yypushback(int number) {
if ( number > yylength() )
zzScanError(ZZ_PUSHBACK_2BIG);
zzMarkedPos -= number;
}
/**
* Resumes scanning until the next regular expression is matched,
* the end of input is encountered or an I/O-Error occurs.
*
* @return the next token
* @exception java.io.IOException if any I/O-Error occurs
*/
public String getNextToken() throws java.io.IOException {
int zzInput;
int zzAction;
// cached fields:
int zzCurrentPosL;
int zzMarkedPosL;
int zzEndReadL = zzEndRead;
char [] zzBufferL = zzBuffer;
char [] zzCMapL = zzcmap_instance;
int [] zzTransL = ZZ_TRANS;
int [] zzRowMapL = ZZ_ROWMAP;
int [] zzAttrL = ZZ_ATTRIBUTE;
while (true) {
zzMarkedPosL = zzMarkedPos;
zzAction = -1;
zzCurrentPosL = zzCurrentPos = zzStartRead = zzMarkedPosL;
zzState = zzLexicalState;
zzForAction: {
while (true) {
if (zzCurrentPosL < zzEndReadL)
zzInput = zzBufferL[zzCurrentPosL++];
else if (zzAtEOF) {
zzInput = YYEOF;
break zzForAction;
}
else {
// store back cached positions
zzCurrentPos = zzCurrentPosL;
zzMarkedPos = zzMarkedPosL;
boolean eof = zzRefill();
// get translated positions and possibly new buffer
zzCurrentPosL = zzCurrentPos;
zzMarkedPosL = zzMarkedPos;
zzBufferL = zzBuffer;
zzEndReadL = zzEndRead;
if (eof) {
zzInput = YYEOF;
break zzForAction;
}
else {
zzInput = zzBufferL[zzCurrentPosL++];
}
}
int zzNext = zzTransL[ zzRowMapL[zzState] + zzCMapL[zzInput] ];
if (zzNext == -1) break zzForAction;
zzState = zzNext;
int zzAttributes = zzAttrL[zzState];
if ( (zzAttributes & 1) == 1 ) {
zzAction = zzState;
zzMarkedPosL = zzCurrentPosL;
if ( (zzAttributes & 8) == 8 ) break zzForAction;
}
}
}
// store back cached position
zzMarkedPos = zzMarkedPosL;
switch (zzAction < 0 ? zzAction : ZZ_ACTION[zzAction]) {
case 2:
{ lines+=addLine;
addLine = 0;
String text = yytext();
if (commentDelims.indexOf(text.charAt(0)) == -1){
yybegin(AFTER);
return(text);
} else {
yybegin(COMMENT);
}
}
case 14: break;
case 8:
{ addLine++;
yybegin(YYINITIAL);
return("");
}
case 15: break;
case 9:
{ yybegin(BEFORE);
return("");
}
case 16: break;
case 4:
{ addLine++;
yybegin(YYINITIAL);
}
case 17: break;
case 5:
{ lines+=addLine;
addLine = 0;
yybegin(BEFORE);
return("");
}
case 18: break;
case 12:
{ lines+=addLine;
addLine = 0;
yybegin(AFTER);
return(unescape(yytext()));
}
case 19: break;
case 7:
{ yybegin(AFTER);
return(yytext());
}
case 20: break;
case 6:
{ lines+=addLine;
addLine = 0;
yybegin(YYINITIAL);
return(yytext());
}
case 21: break;
case 11:
{ yybegin(BEFORE);
}
case 22: break;
case 13:
{ yybegin(AFTER);
return(unescape(yytext()));
}
case 23: break;
case 10:
{ yybegin(YYINITIAL);
return(yytext());
}
case 24: break;
case 1:
{
}
case 25: break;
case 3:
{ lines+=addLine;
addLine = 0;
yybegin(BEFORE);
}
case 26: break;
default:
if (zzInput == YYEOF && zzStartRead == zzCurrentPos) {
zzAtEOF = true;
switch (zzLexicalState) {
case BEFORE: {
yybegin(YYINITIAL);
addLine++;
return("");
}
case 28: break;
default:
return null;
}
}
else {
zzScanError(ZZ_NO_MATCH);
}
}
}
}
}