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The Open Source version of the IBM Toolbox for Java
///////////////////////////////////////////////////////////////////////////////
//
// JTOpen (IBM Toolbox for Java - OSS version)
//
// Filename: JDSQLTokenizer.java
//
// The source code contained herein is licensed under the IBM Public License
// Version 1.0, which has been approved by the Open Source Initiative.
// Copyright (C) 1997-2003 International Business Machines Corporation and
// others. All rights reserved.
//
///////////////////////////////////////////////////////////////////////////////
package com.ibm.as400.access;
import java.util.*;
/**
* This class allows SQL statements to be tokenized without having
* to worry about delimiters appearing in comments. The tokenizer will
* check to make sure the delimiter is not inside a comment before using
* it to separate tokens. This tokenizer behaves much like StringTokenizer.
**/
class JDSQLTokenizer implements Enumeration
{
static final String copyright = "Copyright (C) 1997-2003 International Business Machines Corporation and others.";
/**
Constant containing the default delimiters for SQLTokenizers.
**/
public static final String DEFAULT_DELIMITERS = " \t\n\r\f";
// Performance improvement when using default delimiters.
private static final char[] INTERNAL_DELIMITERS = DEFAULT_DELIMITERS.toCharArray();
/**
Constant indicating the token is a delimiter.
**/
private static final int TOKEN_TYPE_DELIMITER = 1;
/**
Constant indicating the token is a comment.
**/
private static final int TOKEN_TYPE_COMMENT = 2;
/**
Constant indicating the token is a literal.
**/
private static final int TOKEN_TYPE_LITERAL = 4;
/**
Constant indicating the token is part of the SQL statement.
**/
private static final int TOKEN_TYPE_SQL = 8;
private JDSQLToken[] tokens_;
private int numberOfParameters_;
private int currentTokenIndex_;
/**
Constructs a JDSQLTokenizer with the default delimiter
String of " \t\n\r\f".
@param statement SQL statement to tokenize.
**/
public JDSQLTokenizer(String statement)
{
this(statement, DEFAULT_DELIMITERS, true, true);
}
/**
Constructs a JDSQLTokenizer with the specified delimiter
String.
@param statement SQL statement to tokenize.
@param delimiters Set of delimiters to use.
**/
public JDSQLTokenizer(String statement, String delimiters)
{
this(statement, delimiters, true, true);
}
/**
Constructs a JDSQLTokenizer with the specified delimiter String
and the specified delimiter/comment behavior.
@param statement SQL statement to tokenize.
@param delimiters Set of delimiters to use.
@param returnDelimiters true if we should return delimiters as tokens
@param returnComments true if we should return comments as tokens
**/
public JDSQLTokenizer(String statement, String delimiters, boolean returnDelimiters, boolean returnComments)
{
final char[] delims = (DEFAULT_DELIMITERS.equals(delimiters) ? INTERNAL_DELIMITERS : delimiters.toCharArray());
tokens_ = scanForTokens(statement, delims, returnComments, returnDelimiters);
numberOfParameters_ = 0;
for (int i=0; i 0)
{
final int p2 = offset+1;
if (p2 < bufferLen)
{
if (buffer[offset] == '/' && buffer[p2] == '*')
{
++commentDepth;
++offset;
}
else if (buffer[offset] == '*' && buffer[p2] == '/')
{
--commentDepth;
++offset;
}
}
++offset;
}
if (returnComments) token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_COMMENT);
}
else if (p < bufferLen && buffer[offset] == '-' && buffer[p] == '-')
{
// Scan for newline that ends the single-line comment.
int start = offset;
offset = p+1;
while (offset < bufferLen && buffer[offset++] != '\n'){
//loop
}
if (returnComments) token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_COMMENT);
}
else if (buffer[offset] == '\'')
{
// entering single quote
int start = offset;
++offset;
while (offset < bufferLen && buffer[offset++] != '\'') {}
token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_LITERAL);
}
else if (buffer[offset] == '"')
{
// entering double quote
int start = offset;
++offset;
while (offset < bufferLen && buffer[offset++] != '\"') {}
token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_LITERAL);
}
else if (buffer[offset] == '(')
{ //@PDA
// Need to check for case like "insert into x (select ...)" where there is no space after (
// Since no select token was found, the "extended dynamic" package was not being generated.
// So force a token if '(' is matched. Should be ok in all cases that are not delimited since
// they can have a space after '(' anyway.
int start = offset;
++offset;
token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_SQL);
}
else if (isDelimiter(buffer[offset], delimiters))
{
// character at pos is a delimiter
if (returnDelimiters) token = new JDSQLToken(buffer, offset, 1, TOKEN_TYPE_DELIMITER);
++offset;
}
else
{
// character is not any of the above
// scan up to the next delimiter
int numberOfParms = 0;
final int start = offset;
while (offset < bufferLen &&
!isDelimiter(buffer[offset], delimiters) &&
buffer[offset] != '\'' &&
buffer[offset] != '\"')
{
final int p2 = offset+1;
if (p2 < bufferLen &&
((buffer[offset] == '/' && buffer[p2] == '*') ||
(buffer[offset] == '-' && buffer[p2] == '-')))
{
break;
}
else if (buffer[offset] == '?')
{
++numberOfParms;
}
++offset;
}
token = new JDSQLToken(buffer, start, offset-start, TOKEN_TYPE_SQL, numberOfParms);
}
if (token != null) tokens.addToken(token);
}
final JDSQLToken[] jdTokens = new JDSQLToken[tokens.count_];
System.arraycopy(tokens.tokens_, 0, jdTokens, 0, tokens.count_);
return jdTokens;
}
/**
Returns a list of the tokens after scanning the String, with no separators.
@return The String representation of this tokenizer.
**/
public String toString()
{
StringBuffer contents = new StringBuffer();
for (int i=0; i