io.debezium.text.XmlCharacters Maven / Gradle / Ivy
/*
* Copyright Debezium Authors.
*
* Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
*/
package io.debezium.text;
import java.text.CharacterIterator;
import java.text.StringCharacterIterator;
import io.debezium.annotation.Immutable;
/**
* A utility class for determining the validity of various XML names, per the XML 1.0
* Specification.
*
* @author Randall Hauch
*/
@Immutable
public class XmlCharacters {
private static final int NUMBER_OF_CHARACTERS = 1 << 16; // 65536 or 0x10000
/**
* This implementation uses an array that captures for each character the XML classifications. An array is used because it is
* a fast way of looking up each character.
*/
private static final char[] MASKS = new char[NUMBER_OF_CHARACTERS];
private static final int VALID_CHARACTER = 1;
private static final int CONTENT_CHARACTER = 1 << 1;
private static final int SPACE_CHARACTER = 1 << 2;
private static final int NAME_START_CHARACTER = 1 << 3;
private static final int NAME_CHARACTER = 1 << 4;
private static final int NCNAME_START_CHARACTER = 1 << 5;
private static final int NCNAME_CHARACTER = 1 << 6;
private static final int PUBID_CHARACTER = 1 << 7;
static {
// ----------------
// Valid Characters
// ----------------
// [2] Char ::= #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]
// See http://www.w3.org/TR/REC-xml/#charsets
MASKS[0x9] |= VALID_CHARACTER | CONTENT_CHARACTER;
MASKS[0xA] |= VALID_CHARACTER | CONTENT_CHARACTER;
MASKS[0xD] |= VALID_CHARACTER | CONTENT_CHARACTER;
for (int i = 0x20; i <= 0xD7FF; ++i) {
MASKS[i] |= VALID_CHARACTER | CONTENT_CHARACTER;
}
for (int i = 0xE000; i <= 0xFFFD; ++i) {
MASKS[i] |= VALID_CHARACTER | CONTENT_CHARACTER;
}
// Last range is bigger than our character array, so we'll handle in the 'isValid' method ...
// for ( int i=0x10000; i<=0x10FFFF; ++i ) MASKS[i] = VALID_CHARACTER_MASK | CONTENT_CHARACTER;
// Remove the other characters that are not allowed in XML content:
// '<', '&', '\n', '\r', ']'
MASKS['<'] &= ~(CONTENT_CHARACTER);
MASKS['&'] &= ~(CONTENT_CHARACTER);
MASKS['\n'] &= ~(CONTENT_CHARACTER);
MASKS['\r'] &= ~(CONTENT_CHARACTER);
MASKS[']'] &= ~(CONTENT_CHARACTER);
// ---------------------
// Whitespace Characters
// ---------------------
// [3] S ::= (#x20 | #x9 | #xD | #xA)+
// See http://www.w3.org/TR/REC-xml/#sec-common-syn
MASKS[0x20] |= SPACE_CHARACTER;
MASKS[0x9] |= SPACE_CHARACTER;
MASKS[0xA] |= SPACE_CHARACTER;
MASKS[0xD] |= SPACE_CHARACTER;
// ---------------------
// Name Start Characters
// ---------------------
// [4] NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] | [#xD8-#xF6] | [#xF8-#x2FF] |
// [#x370-#x37D] | [#x37F-#x1FFF] | [#x200C-#x200D] | [#x2070-#x218F] |
// [#x2C00-#x2FEF] | [#x3001-#xD7FF] | [#xF900-#xFDCF] | [#xFDF0-#xFFFD] |
// [#x10000-#xEFFFF]
// See http://www.w3.org/TR/REC-xml/#sec-common-syn
//
// Note that all these start characters AND characters are valid for NAME and NCNAME
int nameStartMask = NAME_START_CHARACTER | NCNAME_START_CHARACTER | NAME_CHARACTER | NCNAME_CHARACTER;
MASKS[':'] |= nameStartMask;
MASKS['_'] |= nameStartMask;
for (int i = 'A'; i <= 'Z'; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 'a'; i <= 'z'; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0xC0; i <= 0xD6; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0xD8; i <= 0xF6; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0xF8; i <= 0x2FF; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x370; i <= 0x37D; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x37F; i <= 0x1FFF; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x200C; i <= 0x200D; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x2070; i <= 0x218F; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x2C00; i <= 0x2FEF; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x3001; i <= 0xD7FF; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0xF900; i <= 0xFDCF; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0xFDF0; i <= 0xFFFD; ++i) {
MASKS[i] |= nameStartMask;
}
// Last range is bigger than our character array ...
// for (int i = 0x10000; i <= 0xEFFFF; ++i) MASKS[i] |= nameStartMask;
// ---------------
// Name Characters
// ---------------
// [4a] NameChar ::= NameStartChar | "-" | "." | [0-9] | #xB7 | [#x0300-#x036F] | [#x203F-#x2040]
// See http://www.w3.org/TR/REC-xml/#sec-common-syn
//
// Note that all these characters are valid for NAME and NCNAME
int nameMask = NAME_CHARACTER | NCNAME_CHARACTER;
MASKS['-'] |= nameMask;
MASKS['.'] |= nameMask;
MASKS[0xB7] |= nameMask;
for (int i = '0'; i <= '9'; ++i) {
MASKS[i] |= nameMask;
}
for (int i = 0x0300; i <= 0x036F; ++i) {
MASKS[i] |= nameStartMask;
}
for (int i = 0x203F; i <= 0x2040; ++i) {
MASKS[i] |= nameStartMask;
}
// --------
// NC Names
// --------
// [4] NCName ::= NCNameStartChar NCNameChar*
// which is just an XML Name, minus the ":"
// See http://www.w3.org/TR/REC-xml-names/#ns-decl
// So, remove the NCNAME_CHARACTER and NCNAME_START_CHARACTER masks from ':' ...
MASKS[':'] &= ~(NCNAME_START_CHARACTER | NCNAME_CHARACTER);
// --------------------
// Public ID characters
// --------------------
// [13] PubidChar ::= #x20 | #xD | #xA | [a-zA-Z0-9] | [-'()+,./:=?;!*#@$_%]
MASKS[0x20] |= PUBID_CHARACTER;
MASKS[0xA] |= PUBID_CHARACTER;
MASKS[0xD] |= PUBID_CHARACTER;
for (int i = 'A'; i <= 'Z'; ++i) {
MASKS[i] |= PUBID_CHARACTER;
}
for (int i = 'a'; i <= 'z'; ++i) {
MASKS[i] |= PUBID_CHARACTER;
}
for (int i = '0'; i <= '9'; ++i) {
MASKS[i] |= PUBID_CHARACTER;
}
MASKS['-'] |= PUBID_CHARACTER;
MASKS['\''] |= PUBID_CHARACTER;
MASKS['('] |= PUBID_CHARACTER;
MASKS[')'] |= PUBID_CHARACTER;
MASKS['+'] |= PUBID_CHARACTER;
MASKS[','] |= PUBID_CHARACTER;
MASKS['.'] |= PUBID_CHARACTER;
MASKS['/'] |= PUBID_CHARACTER;
MASKS[':'] |= PUBID_CHARACTER;
MASKS['='] |= PUBID_CHARACTER;
MASKS['?'] |= PUBID_CHARACTER;
MASKS[';'] |= PUBID_CHARACTER;
MASKS['!'] |= PUBID_CHARACTER;
MASKS['*'] |= PUBID_CHARACTER;
MASKS['#'] |= PUBID_CHARACTER;
MASKS['@'] |= PUBID_CHARACTER;
MASKS['$'] |= PUBID_CHARACTER;
MASKS['_'] |= PUBID_CHARACTER;
MASKS['%'] |= PUBID_CHARACTER;
}
private XmlCharacters() {
}
/**
* Determine whether the supplied character is a valid first character in an XML Name. The first character in an XML name is
* more restrictive than the {@link #isValidName(int) remaining characters}.
*
* @param c the character
* @return true if the character is valid for an XML Name's first character
*/
public static boolean isValidNameStart(int c) {
return c < NUMBER_OF_CHARACTERS && (MASKS[c] & NAME_START_CHARACTER) != 0;
}
/**
* Determine whether the supplied character is a valid first character in an XML NCName. The first character in an XML NCName
* is more restrictive than the {@link #isValidName(int) remaining characters}.
*
* @param c the character
* @return true if the character is valid for an XML NCName's first character
*/
public static boolean isValidNcNameStart(int c) {
return c < NUMBER_OF_CHARACTERS && (MASKS[c] & NCNAME_START_CHARACTER) != 0;
}
/**
* Determine whether the supplied character is a valid non-first character in an XML Name. The {@link #isValidNameStart(int)
* first character} in an XML name is more restrictive than the remaining characters.
*
* @param c the character
* @return true if the character is valid character in an XML Name
*/
public static boolean isValidName(int c) {
return c < NUMBER_OF_CHARACTERS && (MASKS[c] & NAME_CHARACTER) != 0;
}
/**
* Determine whether the supplied character is a valid non-first character in an XML NCName. The
* {@link #isValidNcNameStart(int) first character} in an XML NCName is more restrictive than the remaining characters.
*
* @param c the character
* @return true if the character is valid character in an XML NCName
*/
public static boolean isValidNcName(int c) {
return c < NUMBER_OF_CHARACTERS && (MASKS[c] & NCNAME_CHARACTER) != 0;
}
/**
* Determine whether the supplied character is a valid character in an XML Pubid.
*
* @param c the character
* @return true if the character is valid character in an XML Pubid
*/
public static boolean isValidPubid(int c) {
return c < NUMBER_OF_CHARACTERS && (MASKS[c] & PUBID_CHARACTER) != 0;
}
/**
* Determine whether the supplied character is a valid character in XML.
*
* @param c the character
* @return true if the character is valid character in XML
*/
public static boolean isValid(int c) {
return (c < NUMBER_OF_CHARACTERS && (MASKS[c] & VALID_CHARACTER) != 0) || (0x10000 <= c && c <= 0x10FFFF);
}
/**
* Determine whether the supplied character is a valid character in XML content
*
* @param c the character
* @return true if the character is valid character in XML content
*/
public static boolean isValidContent(int c) {
return (c < NUMBER_OF_CHARACTERS && (MASKS[c] & CONTENT_CHARACTER) != 0) || (0x10000 <= c && c <= 0x10FFFF);
}
/**
* Determine whether the supplied character is a valid whitespace character in XML
*
* @param c the character
* @return true if the character is valid whitespace character in XML
*/
public static boolean isValidSpace(int c) {
return c <= 0x20 && (MASKS[c] & SPACE_CHARACTER) != 0;
}
/**
* Determine if the supplied name is a valid XML Name.
*
* @param name the string being checked
* @return true if the supplied name is indeed a valid XML Name, or false otherwise
*/
public static boolean isValidName(String name) {
if (name == null || name.length() == 0) {
return false;
}
CharacterIterator iter = new StringCharacterIterator(name);
char c = iter.first();
if (!isValidNameStart(c)) {
return false;
}
while (c != CharacterIterator.DONE) {
if (!isValidName(c)) {
return false;
}
c = iter.next();
}
return true;
}
/**
* Determine if the supplied name is a valid XML NCName.
*
* @param name the string being checked
* @return true if the supplied name is indeed a valid XML NCName, or false otherwise
*/
public static boolean isValidNcName(String name) {
if (name == null || name.length() == 0) {
return false;
}
CharacterIterator iter = new StringCharacterIterator(name);
char c = iter.first();
if (!isValidNcNameStart(c)) {
return false;
}
while (c != CharacterIterator.DONE) {
if (!isValidNcName(c)) {
return false;
}
c = iter.next();
}
return true;
}
}
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