org.eclipse.jetty.util.LegacyQuotedStringTokenizer Maven / Gradle / Ivy
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//
// ========================================================================
// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
// ========================================================================
//
package org.eclipse.jetty.util;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;
public class LegacyQuotedStringTokenizer implements QuotedStringTokenizer
{
private final String _delim;
private final boolean _returnQuotes;
private final boolean _returnDelimiters;
private final boolean _singleQuotes;
LegacyQuotedStringTokenizer(String delim,
boolean returnDelimiters,
boolean returnQuotes,
boolean singleQuotes)
{
_delim = delim == null ? "\t\n\r" : delim;
_returnDelimiters = returnDelimiters;
_returnQuotes = returnQuotes;
_singleQuotes = singleQuotes;
}
@Override
public Iterator tokenize(String string)
{
LegacyTokenizer tokenizer = new LegacyTokenizer(string);
return new Iterator<>()
{
@Override
public boolean hasNext()
{
return tokenizer.hasMoreTokens();
}
@Override
public String next()
{
return tokenizer.nextToken();
}
};
}
@Override
public boolean needsQuoting(char c)
{
return LegacyTokenizer.needsQuoting(c, _delim);
}
@Override
public String quoteIfNeeded(String s)
{
return LegacyTokenizer.quoteIfNeeded(s, _delim);
}
@Override
public void quoteIfNeeded(StringBuilder buf, String str)
{
LegacyTokenizer.quoteIfNeeded(buf, str, _delim);
}
@Override
public void quote(Appendable buffer, String input)
{
LegacyTokenizer.quote(buffer, input);
}
@Override
public String unquote(String s)
{
return LegacyTokenizer.unquote(s);
}
private class LegacyTokenizer extends StringTokenizer
{
private final String _string;
private final StringBuffer _token;
private boolean _hasToken = false;
private int _i = 0;
public LegacyTokenizer(String str)
{
super("");
_string = str;
if (_delim.indexOf('\'') >= 0 ||
_delim.indexOf('"') >= 0)
throw new Error("Can't use quotes as delimiters: " + _delim);
_token = new StringBuffer(_string.length() > 1024 ? 512 : _string.length() / 2);
}
@Override
public boolean hasMoreTokens()
{
// Already found a token
if (_hasToken)
return true;
int state = 0;
boolean escape = false;
while (_i < _string.length())
{
char c = _string.charAt(_i++);
switch (state)
{
case 0: // Start
if (_delim.indexOf(c) >= 0)
{
if (_returnDelimiters)
{
_token.append(c);
return _hasToken = true;
}
}
else if (c == '\'' && _singleQuotes)
{
if (_returnQuotes)
_token.append(c);
state = 2;
}
else if (c == '\"')
{
if (_returnQuotes)
_token.append(c);
state = 3;
}
else
{
_token.append(c);
_hasToken = true;
state = 1;
}
break;
case 1: // Token
_hasToken = true;
if (_delim.indexOf(c) >= 0)
{
if (_returnDelimiters)
_i--;
return _hasToken;
}
else if (c == '\'' && _singleQuotes)
{
if (_returnQuotes)
_token.append(c);
state = 2;
}
else if (c == '\"')
{
if (_returnQuotes)
_token.append(c);
state = 3;
}
else
{
_token.append(c);
}
break;
case 2: // Single Quote
_hasToken = true;
if (escape)
{
escape = false;
_token.append(c);
}
else if (c == '\'')
{
if (_returnQuotes)
_token.append(c);
state = 1;
}
else if (c == '\\')
{
if (_returnQuotes)
_token.append(c);
escape = true;
}
else
{
_token.append(c);
}
break;
case 3: // Double Quote
_hasToken = true;
if (escape)
{
escape = false;
_token.append(c);
}
else if (c == '\"')
{
if (_returnQuotes)
_token.append(c);
state = 1;
}
else if (c == '\\')
{
if (_returnQuotes)
_token.append(c);
escape = true;
}
else
{
_token.append(c);
}
break;
default:
throw new IllegalStateException();
}
}
return _hasToken;
}
@Override
public String nextToken()
throws NoSuchElementException
{
if (!hasMoreTokens() || _token == null)
throw new NoSuchElementException();
String t = _token.toString();
_token.setLength(0);
_hasToken = false;
return t;
}
@Override
public String nextToken(String delim)
throws NoSuchElementException
{
throw new UnsupportedOperationException();
}
/**
* Not implemented.
*/
@Override
public int countTokens()
{
return -1;
}
public static boolean needsQuoting(char c, String delim)
{
return c == '\\' || c == '"' || c == '\'' || Character.isWhitespace(c) || delim.indexOf(c) >= 0;
}
/**
* Quote a string.
* The string is quoted only if quoting is required due to
* embedded delimiters, quote characters or the
* empty string.
*
* @param s The string to quote.
* @param delim the delimiter to use to quote the string
* @return quoted string
*/
public static String quoteIfNeeded(String s, String delim)
{
if (s == null)
return null;
if (s.length() == 0)
return "\"\"";
for (int i = 0; i < s.length(); i++)
{
char c = s.charAt(i);
if (needsQuoting(c, delim))
{
StringBuffer b = new StringBuffer(s.length() + 8);
quote(b, s);
return b.toString();
}
}
return s;
}
/**
* Append into buf the provided string, adding quotes if needed.
*
* Quoting is determined if any of the characters in the {@code delim} are found in the input {@code str}.
*
* @param buf the buffer to append to
* @param str the string to possibly quote
* @param delim the delimiter characters that will trigger automatic quoting
*/
public static void quoteIfNeeded(StringBuilder buf, String str, String delim)
{
if (str == null)
return;
// check for delimiters in input string
int len = str.length();
if (len == 0)
return;
int ch;
for (int i = 0; i < len; i++)
{
ch = str.codePointAt(i);
if (delim.indexOf(ch) >= 0)
{
// found a delimiter codepoint. we need to quote it.
quote(buf, str);
return;
}
}
// no special delimiters used, no quote needed.
buf.append(str);
}
/**
* Quote a string.
* The string is quoted only if quoting is required due to
* embedded delimiters, quote characters or the
* empty string.
*
* @param s The string to quote.
* @return quoted string
*/
public static String quote(String s)
{
if (s == null)
return null;
if (s.length() == 0)
return "\"\"";
StringBuffer b = new StringBuffer(s.length() + 8);
quote(b, s);
return b.toString();
}
private static final char[] escapes = new char[32];
static
{
Arrays.fill(escapes, (char)0xFFFF);
escapes['\b'] = 'b';
escapes['\t'] = 't';
escapes['\n'] = 'n';
escapes['\f'] = 'f';
escapes['\r'] = 'r';
}
/**
* Quote a string into an Appendable.
* The characters ", \, \n, \r, \t, \f and \b are escaped
*
* @param buffer The Appendable
* @param input The String to quote.
*/
public static void quote(Appendable buffer, String input)
{
if (input == null)
return;
try
{
buffer.append('"');
for (int i = 0; i < input.length(); ++i)
{
char c = input.charAt(i);
if (c >= 32)
{
if (c == '"' || c == '\\')
buffer.append('\\');
buffer.append(c);
}
else
{
char escape = escapes[c];
if (escape == 0xFFFF)
{
// Unicode escape
buffer.append('\\').append('u').append('0').append('0');
if (c < 0x10)
buffer.append('0');
buffer.append(Integer.toString(c, 16));
}
else
{
buffer.append('\\').append(escape);
}
}
}
buffer.append('"');
}
catch (IOException x)
{
throw new RuntimeException(x);
}
}
public static String unquote(String s)
{
return unquote(s, false);
}
/**
* Unquote a string.
*
* @param s The string to unquote.
* @param lenient true if unquoting should be lenient to escaped content, leaving some alone, false if string unescaping
* @return quoted string
*/
public static String unquote(String s, boolean lenient)
{
if (s == null)
return null;
if (s.length() < 2)
return s;
char first = s.charAt(0);
char last = s.charAt(s.length() - 1);
if (first != last || (first != '"' && first != '\''))
return s;
StringBuilder b = new StringBuilder(s.length() - 2);
boolean escape = false;
for (int i = 1; i < s.length() - 1; i++)
{
char c = s.charAt(i);
if (escape)
{
escape = false;
switch (c)
{
case 'n':
b.append('\n');
break;
case 'r':
b.append('\r');
break;
case 't':
b.append('\t');
break;
case 'f':
b.append('\f');
break;
case 'b':
b.append('\b');
break;
case '\\':
b.append('\\');
break;
case '/':
b.append('/');
break;
case '"':
b.append('"');
break;
case 'u':
b.append((char)(
(TypeUtil.convertHexDigit((byte)s.charAt(i++)) << 24) +
(TypeUtil.convertHexDigit((byte)s.charAt(i++)) << 16) +
(TypeUtil.convertHexDigit((byte)s.charAt(i++)) << 8) +
(TypeUtil.convertHexDigit((byte)s.charAt(i++)))
)
);
break;
default:
if (lenient && !isValidEscaping(c))
{
b.append('\\');
}
b.append(c);
}
}
else if (c == '\\')
{
escape = true;
}
else
{
b.append(c);
}
}
return b.toString();
}
/**
* Check that char c (which is preceded by a backslash) is a valid
* escape sequence.
*/
private static boolean isValidEscaping(char c)
{
return ((c == 'n') || (c == 'r') || (c == 't') ||
(c == 'f') || (c == 'b') || (c == '\\') ||
(c == '/') || (c == '"') || (c == 'u'));
}
}
}