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8187443: Forest Consolidation: Move files to unified layout
Reviewed-by: darcy, ihse
This commit is contained in:
Erik Joelsson
parent
270fe13182
commit
3789983e89
56923 changed files with 3 additions and 15727 deletions
627
src/java.base/share/classes/sun/invoke/util/BytecodeName.java
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627
src/java.base/share/classes/sun/invoke/util/BytecodeName.java
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@ -0,0 +1,627 @@
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/*
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* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
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*
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||||
* This code is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 only, as
|
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* published by the Free Software Foundation. Oracle designates this
|
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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||||
* This code 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
|
||||
* version 2 for more details (a copy is included in the LICENSE file that
|
||||
* accompanied this code).
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License version
|
||||
* 2 along with this work; if not, write to the Free Software Foundation,
|
||||
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
||||
*
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||||
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package sun.invoke.util;
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/**
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* Utility routines for dealing with bytecode-level names.
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* Includes universal mangling rules for the JVM.
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*
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* <h3>Avoiding Dangerous Characters </h3>
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*
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* <p>
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* The JVM defines a very small set of characters which are illegal
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* in name spellings. We will slightly extend and regularize this set
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* into a group of <cite>dangerous characters</cite>.
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* These characters will then be replaced, in mangled names, by escape sequences.
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* In addition, accidental escape sequences must be further escaped.
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* Finally, a special prefix will be applied if and only if
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* the mangling would otherwise fail to begin with the escape character.
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* This happens to cover the corner case of the null string,
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* and also clearly marks symbols which need demangling.
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* </p>
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* <p>
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* Dangerous characters are the union of all characters forbidden
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* or otherwise restricted by the JVM specification,
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* plus their mates, if they are brackets
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* (<code><big><b>[</b></big></code> and <code><big><b>]</b></big></code>,
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* <code><big><b><</b></big></code> and <code><big><b>></b></big></code>),
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* plus, arbitrarily, the colon character <code><big><b>:</b></big></code>.
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* There is no distinction between type, method, and field names.
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* This makes it easier to convert between mangled names of different
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* types, since they do not need to be decoded (demangled).
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* </p>
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* <p>
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* The escape character is backslash <code><big><b>\</b></big></code>
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* (also known as reverse solidus).
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* This character is, until now, unheard of in bytecode names,
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* but traditional in the proposed role.
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*
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* </p>
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* <h3> Replacement Characters </h3>
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*
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*
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* <p>
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* Every escape sequence is two characters
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* (in fact, two UTF8 bytes) beginning with
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* the escape character and followed by a
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* <cite>replacement character</cite>.
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* (Since the replacement character is never a backslash,
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* iterated manglings do not double in size.)
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* </p>
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* <p>
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* Each dangerous character has some rough visual similarity
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* to its corresponding replacement character.
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* This makes mangled symbols easier to recognize by sight.
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* </p>
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* <p>
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* The dangerous characters are
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* <code><big><b>/</b></big></code> (forward slash, used to delimit package components),
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* <code><big><b>.</b></big></code> (dot, also a package delimiter),
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* <code><big><b>;</b></big></code> (semicolon, used in signatures),
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* <code><big><b>$</b></big></code> (dollar, used in inner classes and synthetic members),
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* <code><big><b><</b></big></code> (left angle),
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* <code><big><b>></b></big></code> (right angle),
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* <code><big><b>[</b></big></code> (left square bracket, used in array types),
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* <code><big><b>]</b></big></code> (right square bracket, reserved in this scheme for language use),
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* and <code><big><b>:</b></big></code> (colon, reserved in this scheme for language use).
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* Their replacements are, respectively,
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* <code><big><b>|</b></big></code> (vertical bar),
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* <code><big><b>,</b></big></code> (comma),
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* <code><big><b>?</b></big></code> (question mark),
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* <code><big><b>%</b></big></code> (percent),
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* <code><big><b>^</b></big></code> (caret),
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* <code><big><b>_</b></big></code> (underscore), and
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* <code><big><b>{</b></big></code> (left curly bracket),
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* <code><big><b>}</b></big></code> (right curly bracket),
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* <code><big><b>!</b></big></code> (exclamation mark).
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* In addition, the replacement character for the escape character itself is
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* <code><big><b>-</b></big></code> (hyphen),
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* and the replacement character for the null prefix is
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* <code><big><b>=</b></big></code> (equal sign).
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* </p>
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* <p>
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* An escape character <code><big><b>\</b></big></code>
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* followed by any of these replacement characters
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* is an escape sequence, and there are no other escape sequences.
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* An equal sign is only part of an escape sequence
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* if it is the second character in the whole string, following a backslash.
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* Two consecutive backslashes do <em>not</em> form an escape sequence.
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* </p>
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* <p>
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* Each escape sequence replaces a so-called <cite>original character</cite>
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* which is either one of the dangerous characters or the escape character.
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* A null prefix replaces an initial null string, not a character.
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* </p>
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* <p>
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* All this implies that escape sequences cannot overlap and may be
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* determined all at once for a whole string. Note that a spelling
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* string can contain <cite>accidental escapes</cite>, apparent escape
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* sequences which must not be interpreted as manglings.
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* These are disabled by replacing their leading backslash with an
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* escape sequence (<code><big><b>\-</b></big></code>). To mangle a string, three logical steps
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* are required, though they may be carried out in one pass:
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* </p>
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* <ol>
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* <li>In each accidental escape, replace the backslash with an escape sequence
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* (<code><big><b>\-</b></big></code>).</li>
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* <li>Replace each dangerous character with an escape sequence
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* (<code><big><b>\|</b></big></code> for <code><big><b>/</b></big></code>, etc.).</li>
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* <li>If the first two steps introduced any change, <em>and</em>
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* if the string does not already begin with a backslash, prepend a null prefix (<code><big><b>\=</b></big></code>).</li>
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* </ol>
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*
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* To demangle a mangled string that begins with an escape,
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* remove any null prefix, and then replace (in parallel)
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* each escape sequence by its original character.
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* <p>Spelling strings which contain accidental
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* escapes <em>must</em> have them replaced, even if those
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* strings do not contain dangerous characters.
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* This restriction means that mangling a string always
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* requires a scan of the string for escapes.
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* But then, a scan would be required anyway,
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* to check for dangerous characters.
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*
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* </p>
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* <h3> Nice Properties </h3>
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*
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* <p>
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* If a bytecode name does not contain any escape sequence,
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* demangling is a no-op: The string demangles to itself.
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* Such a string is called <cite>self-mangling</cite>.
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* Almost all strings are self-mangling.
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* In practice, to demangle almost any name “found in nature”,
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* simply verify that it does not begin with a backslash.
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* </p>
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* <p>
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* Mangling is a one-to-one function, while demangling
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* is a many-to-one function.
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* A mangled string is defined as <cite>validly mangled</cite> if
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* it is in fact the unique mangling of its spelling string.
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* Three examples of invalidly mangled strings are <code><big><b>\=foo</b></big></code>,
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* <code><big><b>\-bar</b></big></code>, and <code><big><b>baz\!</b></big></code>, which demangle to <code><big><b>foo</b></big></code>, <code><big><b>\bar</b></big></code>, and
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* <code><big><b>baz\!</b></big></code>, but then remangle to <code><big><b>foo</b></big></code>, <code><big><b>\bar</b></big></code>, and <code><big><b>\=baz\-!</b></big></code>.
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* If a language back-end or runtime is using mangled names,
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* it should never present an invalidly mangled bytecode
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* name to the JVM. If the runtime encounters one,
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* it should also report an error, since such an occurrence
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* probably indicates a bug in name encoding which
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* will lead to errors in linkage.
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* However, this note does not propose that the JVM verifier
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* detect invalidly mangled names.
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* </p>
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* <p>
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* As a result of these rules, it is a simple matter to
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* compute validly mangled substrings and concatenations
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* of validly mangled strings, and (with a little care)
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* these correspond to corresponding operations on their
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* spelling strings.
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* </p>
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* <ul>
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* <li>Any prefix of a validly mangled string is also validly mangled,
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* although a null prefix may need to be removed.</li>
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* <li>Any suffix of a validly mangled string is also validly mangled,
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* although a null prefix may need to be added.</li>
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* <li>Two validly mangled strings, when concatenated,
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* are also validly mangled, although any null prefix
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* must be removed from the second string,
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* and a trailing backslash on the first string may need escaping,
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* if it would participate in an accidental escape when followed
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* by the first character of the second string.</li>
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* </ul>
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* <p>If languages that include non-Java symbol spellings use this
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* mangling convention, they will enjoy the following advantages:
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* </p>
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* <ul>
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* <li>They can interoperate via symbols they share in common.</li>
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* <li>Low-level tools, such as backtrace printers, will have readable displays.</li>
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* <li>Future JVM and language extensions can safely use the dangerous characters
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* for structuring symbols, but will never interfere with valid spellings.</li>
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* <li>Runtimes and compilers can use standard libraries for mangling and demangling.</li>
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* <li>Occasional transliterations and name composition will be simple and regular,
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* for classes, methods, and fields.</li>
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* <li>Bytecode names will continue to be compact.
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* When mangled, spellings will at most double in length, either in
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* UTF8 or UTF16 format, and most will not change at all.</li>
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* </ul>
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*
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*
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* <h3> Suggestions for Human Readable Presentations </h3>
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*
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*
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* <p>
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* For human readable displays of symbols,
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* it will be better to present a string-like quoted
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* representation of the spelling, because JVM users
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* are generally familiar with such tokens.
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* We suggest using single or double quotes before and after
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* mangled symbols which are not valid Java identifiers,
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* with quotes, backslashes, and non-printing characters
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* escaped as if for literals in the Java language.
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* </p>
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* <p>
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* For example, an HTML-like spelling
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* <code><big><b><pre></b></big></code> mangles to
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* <code><big><b>\^pre\_</b></big></code> and could
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* display more cleanly as
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* <code><big><b>'<pre>'</b></big></code>,
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* with the quotes included.
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* Such string-like conventions are <em>not</em> suitable
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* for mangled bytecode names, in part because
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* dangerous characters must be eliminated, rather
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* than just quoted. Otherwise internally structured
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* strings like package prefixes and method signatures
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* could not be reliably parsed.
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* </p>
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* <p>
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* In such human-readable displays, invalidly mangled
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* names should <em>not</em> be demangled and quoted,
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* for this would be misleading. Likewise, JVM symbols
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* which contain dangerous characters (like dots in field
|
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* names or brackets in method names) should not be
|
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* simply quoted. The bytecode names
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* <code><big><b>\=phase\,1</b></big></code> and
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* <code><big><b>phase.1</b></big></code> are distinct,
|
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* and in demangled displays they should be presented as
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* <code><big><b>'phase.1'</b></big></code> and something like
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* <code><big><b>'phase'.1</b></big></code>, respectively.
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* </p>
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*
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* @author John Rose
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* @version 1.2, 02/06/2008
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* @see http://blogs.sun.com/jrose/entry/symbolic_freedom_in_the_vm
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*/
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public class BytecodeName {
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private BytecodeName() { } // static only class
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/** Given a source name, produce the corresponding bytecode name.
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* The source name should not be qualified, because any syntactic
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* markers (dots, slashes, dollar signs, colons, etc.) will be mangled.
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* @param s the source name
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* @return a valid bytecode name which represents the source name
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*/
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public static String toBytecodeName(String s) {
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String bn = mangle(s);
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assert((Object)bn == s || looksMangled(bn)) : bn;
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assert(s.equals(toSourceName(bn))) : s;
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return bn;
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}
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/** Given an unqualified bytecode name, produce the corresponding source name.
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* The bytecode name must not contain dangerous characters.
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* In particular, it must not be qualified or segmented by colon {@code ':'}.
|
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* @param s the bytecode name
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* @return the source name, which may possibly have unsafe characters
|
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* @throws IllegalArgumentException if the bytecode name is not {@link #isSafeBytecodeName safe}
|
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* @see #isSafeBytecodeName(java.lang.String)
|
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*/
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public static String toSourceName(String s) {
|
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checkSafeBytecodeName(s);
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String sn = s;
|
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if (looksMangled(s)) {
|
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sn = demangle(s);
|
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assert(s.equals(mangle(sn))) : s+" => "+sn+" => "+mangle(sn);
|
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}
|
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return sn;
|
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}
|
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|
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/**
|
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* Given a bytecode name from a classfile, separate it into
|
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* components delimited by dangerous characters.
|
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* Each resulting array element will be either a dangerous character,
|
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* or else a safe bytecode name.
|
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* (The safe name might possibly be mangled to hide further dangerous characters.)
|
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* For example, the qualified class name {@code java/lang/String}
|
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* will be parsed into the array {@code {"java", '/', "lang", '/', "String"}}.
|
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* The name {@code <init>} will be parsed into {@code {'<', "init", '>'}}.
|
||||
* The name {@code foo/bar$:baz} will be parsed into
|
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* {@code {"foo", '/', "bar", '$', ':', "baz"}}.
|
||||
* The name {@code ::\=:foo:\=bar\!baz} will be parsed into
|
||||
* {@code {':', ':', "", ':', "foo", ':', "bar:baz"}}.
|
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*/
|
||||
public static Object[] parseBytecodeName(String s) {
|
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int slen = s.length();
|
||||
Object[] res = null;
|
||||
for (int pass = 0; pass <= 1; pass++) {
|
||||
int fillp = 0;
|
||||
int lasti = 0;
|
||||
for (int i = 0; i <= slen; i++) {
|
||||
int whichDC = -1;
|
||||
if (i < slen) {
|
||||
whichDC = DANGEROUS_CHARS.indexOf(s.charAt(i));
|
||||
if (whichDC < DANGEROUS_CHAR_FIRST_INDEX) continue;
|
||||
}
|
||||
// got to end of string or next dangerous char
|
||||
if (lasti < i) {
|
||||
// normal component
|
||||
if (pass != 0)
|
||||
res[fillp] = toSourceName(s.substring(lasti, i));
|
||||
fillp++;
|
||||
lasti = i+1;
|
||||
}
|
||||
if (whichDC >= DANGEROUS_CHAR_FIRST_INDEX) {
|
||||
if (pass != 0)
|
||||
res[fillp] = DANGEROUS_CHARS_CA[whichDC];
|
||||
fillp++;
|
||||
lasti = i+1;
|
||||
}
|
||||
}
|
||||
if (pass != 0) break;
|
||||
// between passes, build the result array
|
||||
res = new Object[fillp];
|
||||
if (fillp <= 1 && lasti == 0) {
|
||||
if (fillp != 0) res[0] = toSourceName(s);
|
||||
break;
|
||||
}
|
||||
}
|
||||
return res;
|
||||
}
|
||||
|
||||
/**
|
||||
* Given a series of components, create a bytecode name for a classfile.
|
||||
* This is the inverse of {@link #parseBytecodeName(java.lang.String)}.
|
||||
* Each component must either be an interned one-character string of
|
||||
* a dangerous character, or else a safe bytecode name.
|
||||
* @param components a series of name components
|
||||
* @return the concatenation of all components
|
||||
* @throws IllegalArgumentException if any component contains an unsafe
|
||||
* character, and is not an interned one-character string
|
||||
* @throws NullPointerException if any component is null
|
||||
*/
|
||||
public static String unparseBytecodeName(Object[] components) {
|
||||
Object[] components0 = components;
|
||||
for (int i = 0; i < components.length; i++) {
|
||||
Object c = components[i];
|
||||
if (c instanceof String) {
|
||||
String mc = toBytecodeName((String) c);
|
||||
if (i == 0 && components.length == 1)
|
||||
return mc; // usual case
|
||||
if ((Object)mc != c) {
|
||||
if (components == components0)
|
||||
components = components.clone();
|
||||
components[i] = c = mc;
|
||||
}
|
||||
}
|
||||
}
|
||||
return appendAll(components);
|
||||
}
|
||||
private static String appendAll(Object[] components) {
|
||||
if (components.length <= 1) {
|
||||
if (components.length == 1) {
|
||||
return String.valueOf(components[0]);
|
||||
}
|
||||
return "";
|
||||
}
|
||||
int slen = 0;
|
||||
for (Object c : components) {
|
||||
if (c instanceof String)
|
||||
slen += String.valueOf(c).length();
|
||||
else
|
||||
slen += 1;
|
||||
}
|
||||
StringBuilder sb = new StringBuilder(slen);
|
||||
for (Object c : components) {
|
||||
sb.append(c);
|
||||
}
|
||||
return sb.toString();
|
||||
}
|
||||
|
||||
/**
|
||||
* Given a bytecode name, produce the corresponding display name.
|
||||
* This is the source name, plus quotes if needed.
|
||||
* If the bytecode name contains dangerous characters,
|
||||
* assume that they are being used as punctuation,
|
||||
* and pass them through unchanged.
|
||||
* Non-empty runs of non-dangerous characters are demangled
|
||||
* if necessary, and the resulting names are quoted if
|
||||
* they are not already valid Java identifiers, or if
|
||||
* they contain a dangerous character (i.e., dollar sign "$").
|
||||
* Single quotes are used when quoting.
|
||||
* Within quoted names, embedded single quotes and backslashes
|
||||
* are further escaped by prepended backslashes.
|
||||
*
|
||||
* @param s the original bytecode name (which may be qualified)
|
||||
* @return a human-readable presentation
|
||||
*/
|
||||
public static String toDisplayName(String s) {
|
||||
Object[] components = parseBytecodeName(s);
|
||||
for (int i = 0; i < components.length; i++) {
|
||||
if (!(components[i] instanceof String))
|
||||
continue;
|
||||
String sn = (String) components[i];
|
||||
// note that the name is already demangled!
|
||||
//sn = toSourceName(sn);
|
||||
if (!isJavaIdent(sn) || sn.indexOf('$') >=0 ) {
|
||||
components[i] = quoteDisplay(sn);
|
||||
}
|
||||
}
|
||||
return appendAll(components);
|
||||
}
|
||||
private static boolean isJavaIdent(String s) {
|
||||
int slen = s.length();
|
||||
if (slen == 0) return false;
|
||||
if (!Character.isJavaIdentifierStart(s.charAt(0)))
|
||||
return false;
|
||||
for (int i = 1; i < slen; i++) {
|
||||
if (!Character.isJavaIdentifierPart(s.charAt(i)))
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
private static String quoteDisplay(String s) {
|
||||
// TO DO: Replace wierd characters in s by C-style escapes.
|
||||
return "'"+s.replaceAll("['\\\\]", "\\\\$0")+"'";
|
||||
}
|
||||
|
||||
private static void checkSafeBytecodeName(String s)
|
||||
throws IllegalArgumentException {
|
||||
if (!isSafeBytecodeName(s)) {
|
||||
throw new IllegalArgumentException(s);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Report whether a simple name is safe as a bytecode name.
|
||||
* Such names are acceptable in class files as class, method, and field names.
|
||||
* Additionally, they are free of "dangerous" characters, even if those
|
||||
* characters are legal in some (or all) names in class files.
|
||||
* @param s the proposed bytecode name
|
||||
* @return true if the name is non-empty and all of its characters are safe
|
||||
*/
|
||||
public static boolean isSafeBytecodeName(String s) {
|
||||
if (s.length() == 0) return false;
|
||||
// check occurrences of each DANGEROUS char
|
||||
for (char xc : DANGEROUS_CHARS_A) {
|
||||
if (xc == ESCAPE_C) continue; // not really that dangerous
|
||||
if (s.indexOf(xc) >= 0) return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
/**
|
||||
* Report whether a character is safe in a bytecode name.
|
||||
* This is true of any unicode character except the following
|
||||
* <em>dangerous characters</em>: {@code ".;:$[]<>/"}.
|
||||
* @param c the proposed character
|
||||
* @return true if the character is safe to use in classfiles
|
||||
*/
|
||||
public static boolean isSafeBytecodeChar(char c) {
|
||||
return DANGEROUS_CHARS.indexOf(c) < DANGEROUS_CHAR_FIRST_INDEX;
|
||||
}
|
||||
|
||||
private static boolean looksMangled(String s) {
|
||||
return s.charAt(0) == ESCAPE_C;
|
||||
}
|
||||
|
||||
private static String mangle(String s) {
|
||||
if (s.length() == 0)
|
||||
return NULL_ESCAPE;
|
||||
|
||||
// build this lazily, when we first need an escape:
|
||||
StringBuilder sb = null;
|
||||
|
||||
for (int i = 0, slen = s.length(); i < slen; i++) {
|
||||
char c = s.charAt(i);
|
||||
|
||||
boolean needEscape = false;
|
||||
if (c == ESCAPE_C) {
|
||||
if (i+1 < slen) {
|
||||
char c1 = s.charAt(i+1);
|
||||
if ((i == 0 && c1 == NULL_ESCAPE_C)
|
||||
|| c1 != originalOfReplacement(c1)) {
|
||||
// an accidental escape
|
||||
needEscape = true;
|
||||
}
|
||||
}
|
||||
} else {
|
||||
needEscape = isDangerous(c);
|
||||
}
|
||||
|
||||
if (!needEscape) {
|
||||
if (sb != null) sb.append(c);
|
||||
continue;
|
||||
}
|
||||
|
||||
// build sb if this is the first escape
|
||||
if (sb == null) {
|
||||
sb = new StringBuilder(s.length()+10);
|
||||
// mangled names must begin with a backslash:
|
||||
if (s.charAt(0) != ESCAPE_C && i > 0)
|
||||
sb.append(NULL_ESCAPE);
|
||||
// append the string so far, which is unremarkable:
|
||||
sb.append(s, 0, i);
|
||||
}
|
||||
|
||||
// rewrite \ to \-, / to \|, etc.
|
||||
sb.append(ESCAPE_C);
|
||||
sb.append(replacementOf(c));
|
||||
}
|
||||
|
||||
if (sb != null) return sb.toString();
|
||||
|
||||
return s;
|
||||
}
|
||||
|
||||
private static String demangle(String s) {
|
||||
// build this lazily, when we first meet an escape:
|
||||
StringBuilder sb = null;
|
||||
|
||||
int stringStart = 0;
|
||||
if (s.startsWith(NULL_ESCAPE))
|
||||
stringStart = 2;
|
||||
|
||||
for (int i = stringStart, slen = s.length(); i < slen; i++) {
|
||||
char c = s.charAt(i);
|
||||
|
||||
if (c == ESCAPE_C && i+1 < slen) {
|
||||
// might be an escape sequence
|
||||
char rc = s.charAt(i+1);
|
||||
char oc = originalOfReplacement(rc);
|
||||
if (oc != rc) {
|
||||
// build sb if this is the first escape
|
||||
if (sb == null) {
|
||||
sb = new StringBuilder(s.length());
|
||||
// append the string so far, which is unremarkable:
|
||||
sb.append(s, stringStart, i);
|
||||
}
|
||||
++i; // skip both characters
|
||||
c = oc;
|
||||
}
|
||||
}
|
||||
|
||||
if (sb != null)
|
||||
sb.append(c);
|
||||
}
|
||||
|
||||
if (sb != null) return sb.toString();
|
||||
|
||||
return s.substring(stringStart);
|
||||
}
|
||||
|
||||
static char ESCAPE_C = '\\';
|
||||
// empty escape sequence to avoid a null name or illegal prefix
|
||||
static char NULL_ESCAPE_C = '=';
|
||||
static String NULL_ESCAPE = ESCAPE_C+""+NULL_ESCAPE_C;
|
||||
|
||||
static final String DANGEROUS_CHARS = "\\/.;:$[]<>"; // \\ must be first
|
||||
static final String REPLACEMENT_CHARS = "-|,?!%{}^_";
|
||||
static final int DANGEROUS_CHAR_FIRST_INDEX = 1; // index after \\
|
||||
static char[] DANGEROUS_CHARS_A = DANGEROUS_CHARS.toCharArray();
|
||||
static char[] REPLACEMENT_CHARS_A = REPLACEMENT_CHARS.toCharArray();
|
||||
static final Character[] DANGEROUS_CHARS_CA;
|
||||
static {
|
||||
Character[] dcca = new Character[DANGEROUS_CHARS.length()];
|
||||
for (int i = 0; i < dcca.length; i++)
|
||||
dcca[i] = Character.valueOf(DANGEROUS_CHARS.charAt(i));
|
||||
DANGEROUS_CHARS_CA = dcca;
|
||||
}
|
||||
|
||||
static final long[] SPECIAL_BITMAP = new long[2]; // 128 bits
|
||||
static {
|
||||
String SPECIAL = DANGEROUS_CHARS + REPLACEMENT_CHARS;
|
||||
//System.out.println("SPECIAL = "+SPECIAL);
|
||||
for (char c : SPECIAL.toCharArray()) {
|
||||
SPECIAL_BITMAP[c >>> 6] |= 1L << c;
|
||||
}
|
||||
}
|
||||
static boolean isSpecial(char c) {
|
||||
if ((c >>> 6) < SPECIAL_BITMAP.length)
|
||||
return ((SPECIAL_BITMAP[c >>> 6] >> c) & 1) != 0;
|
||||
else
|
||||
return false;
|
||||
}
|
||||
static char replacementOf(char c) {
|
||||
if (!isSpecial(c)) return c;
|
||||
int i = DANGEROUS_CHARS.indexOf(c);
|
||||
if (i < 0) return c;
|
||||
return REPLACEMENT_CHARS.charAt(i);
|
||||
}
|
||||
static char originalOfReplacement(char c) {
|
||||
if (!isSpecial(c)) return c;
|
||||
int i = REPLACEMENT_CHARS.indexOf(c);
|
||||
if (i < 0) return c;
|
||||
return DANGEROUS_CHARS.charAt(i);
|
||||
}
|
||||
static boolean isDangerous(char c) {
|
||||
if (!isSpecial(c)) return false;
|
||||
return (DANGEROUS_CHARS.indexOf(c) >= DANGEROUS_CHAR_FIRST_INDEX);
|
||||
}
|
||||
static int indexOfDangerousChar(String s, int from) {
|
||||
for (int i = from, slen = s.length(); i < slen; i++) {
|
||||
if (isDangerous(s.charAt(i)))
|
||||
return i;
|
||||
}
|
||||
return -1;
|
||||
}
|
||||
static int lastIndexOfDangerousChar(String s, int from) {
|
||||
for (int i = Math.min(from, s.length()-1); i >= 0; i--) {
|
||||
if (isDangerous(s.charAt(i)))
|
||||
return i;
|
||||
}
|
||||
return -1;
|
||||
}
|
||||
|
||||
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue