android-34/android/icu/impl/RuleCharacterIterator.java - platform/prebuilts/fullsdk/sources - Git at Google

 /* GENERATED SOURCE. DO NOT MODIFY. */
 // © 2016 and later: Unicode, Inc. and others.
 // License & terms of use: http://www.unicode.org/copyright.html
 /*
 **********************************************************************
 * Copyright (c) 2003-2011, International Business Machines
 * Corporation and others.  All Rights Reserved.
 **********************************************************************
 * Author: Alan Liu
 * Created: September 23 2003
 * Since: ICU 2.8
 **********************************************************************
 */
 package android.icu.impl;

 import java.text.ParsePosition;

 import android.icu.text.SymbolTable;
 import android.icu.text.UTF16;

 /**
  * An iterator that returns 32-bit code points.  This class is deliberately
  * <em>not</em> related to any of the JDK or ICU4J character iterator classes
  * in order to minimize complexity.
  * @author Alan Liu
  * @hide Only a subset of ICU is exposed in Android
  */
 public class RuleCharacterIterator {

     // TODO: Ideas for later.  (Do not implement if not needed, lest the
     // code coverage numbers go down due to unused methods.)
     // 1. Add a copy constructor, equals() method, clone() method.
     // 2. Rather than return DONE, throw an exception if the end
     // is reached -- this is an alternate usage model, probably not useful.
     // 3. Return isEscaped from next().  If this happens,
     // don't keep an isEscaped member variable.

     /**
      * Text being iterated.
      */
     private String text;

     /**
      * Position of iterator.
      */
     private ParsePosition pos;

     /**
      * Symbol table used to parse and dereference variables.  May be null.
      */
     private SymbolTable sym;

     /**
      * Current variable expansion, or null if none.
      */
     private String buf;

     /**
      * Position within buf[].  Meaningless if buf == null.
      */
     private int bufPos;

     /**
      * Flag indicating whether the last character was parsed from an escape.
      */
     private boolean isEscaped;

     /**
      * Value returned when there are no more characters to iterate.
      */
     public static final int DONE = -1;

     /**
      * Bitmask option to enable parsing of variable names.  If (options &
      * PARSE_VARIABLES) != 0, then an embedded variable will be expanded to
      * its value.  Variables are parsed using the SymbolTable API.
      */
     public static final int PARSE_VARIABLES = 1;

     /**
      * Bitmask option to enable parsing of escape sequences.  If (options &
      * PARSE_ESCAPES) != 0, then an embedded escape sequence will be expanded
      * to its value.  Escapes are parsed using Utility.unescapeAndLengthAt().
      */
     public static final int PARSE_ESCAPES   = 2;

     /**
      * Bitmask option to enable skipping of whitespace.  If (options &
      * SKIP_WHITESPACE) != 0, then Unicode Pattern_White_Space characters will be silently
      * skipped, as if they were not present in the input.
      */
     public static final int SKIP_WHITESPACE = 4;

     /** For use with {@link #getPos(Position)} & {@link #setPos(Position)}.
      * @hide Only a subset of ICU is exposed in Android*/
     public static final class Position {
         private String buf;
         private int bufPos;
         private int posIndex;
     };

     /**
      * Constructs an iterator over the given text, starting at the given
      * position.
      * @param text the text to be iterated
      * @param sym the symbol table, or null if there is none.  If sym is null,
      * then variables will not be dereferenced, even if the PARSE_VARIABLES
      * option is set.
      * @param pos upon input, the index of the next character to return.  If a
      * variable has been dereferenced, then pos will <em>not</em> increment as
      * characters of the variable value are iterated.
      */
     public RuleCharacterIterator(String text, SymbolTable sym,
                                  ParsePosition pos) {
         if (text == null || pos.getIndex() > text.length()) {
             throw new IllegalArgumentException();
         }
         this.text = text;
         this.sym = sym;
         this.pos = pos;
         buf = null;
     }

     /**
      * Returns true if this iterator has no more characters to return.
      */
     public boolean atEnd() {
         return buf == null && pos.getIndex() == text.length();
     }

     /**
      * Returns the next character using the given options, or DONE if there
      * are no more characters, and advance the position to the next
      * character.
      * @param options one or more of the following options, bitwise-OR-ed
      * together: PARSE_VARIABLES, PARSE_ESCAPES, SKIP_WHITESPACE.
      * @return the current 32-bit code point, or DONE
      */
     public int next(int options) {
         int c = DONE;
         isEscaped = false;

         for (;;) {
             c = _current();
             _advance(UTF16.getCharCount(c));

             if (c == SymbolTable.SYMBOL_REF && buf == null &&
                 (options & PARSE_VARIABLES) != 0 && sym != null) {
                 String name = sym.parseReference(text, pos, text.length());
                 // If name == null there was an isolated SYMBOL_REF;
                 // return it.  Caller must be prepared for this.
                 if (name == null) {
                     break;
                 }
                 bufPos = 0;
                 char[] chars = sym.lookup(name);
                 if (chars == null) {
                     buf = null;
                     throw new IllegalArgumentException(
                                 "Undefined variable: " + name);
                 }
                 // Handle empty variable value
                 if (chars.length == 0) {
                     buf = null;
                 }
                 buf = new String(chars);
                 continue;
             }

             if ((options & SKIP_WHITESPACE) != 0 &&
                 PatternProps.isWhiteSpace(c)) {
                 continue;
             }

             if (c == '\\' && (options & PARSE_ESCAPES) != 0) {
                 int cpAndLength = Utility.unescapeAndLengthAt(
                         getCurrentBuffer(), getCurrentBufferPos());
                 if (cpAndLength < 0) {
                     throw new IllegalArgumentException("Invalid escape");
                 }
                 c = Utility.cpFromCodePointAndLength(cpAndLength);
                 jumpahead(Utility.lengthFromCodePointAndLength(cpAndLength));
                 isEscaped = true;
             }

             break;
         }

         return c;
     }

     /**
      * Returns true if the last character returned by next() was
      * escaped.  This will only be the case if the option passed in to
      * next() included PARSE_ESCAPED and the next character was an
      * escape sequence.
      */
     public boolean isEscaped() {
         return isEscaped;
     }

     /**
      * Returns true if this iterator is currently within a variable expansion.
      */
     public boolean inVariable() {
         return buf != null;
     }

     /**
      * Returns an object which, when later passed to setPos(), will
      * restore this iterator's position.  Usage idiom:
      *
      * RuleCharacterIterator iterator = ...;
      * Position pos = iterator.getPos(null); // allocate position object
      * for (;;) {
      *   pos = iterator.getPos(pos); // reuse position object
      *   int c = iterator.next(...);
      *   ...
      * }
      * iterator.setPos(pos);
      *
      * @param p a position object previously returned by getPos(),
      * or null.  If not null, it will be updated and returned.  If
      * null, a new position object will be allocated and returned.
      * @return a position object which may be passed to setPos(),
      * either `p,' or if `p' == null, a newly-allocated object
      */
     public Position getPos(Position p) {
         if (p == null) {
             p = new Position();
         }
         p.buf = buf;
         p.bufPos = bufPos;
         p.posIndex = pos.getIndex();
         return p;
     }

     /**
      * Restores this iterator to the position it had when getPos()
      * returned the given object.
      * @param p a position object previously returned by getPos()
      */
     public void setPos(Position p) {
         buf = p.buf;
         pos.setIndex(p.posIndex);
         bufPos = p.bufPos;
     }

     /**
      * Skips ahead past any ignored characters, as indicated by the given
      * options.  This is useful in conjunction with the lookahead() method.
      *
      * Currently, this only has an effect for SKIP_WHITESPACE.
      * @param options one or more of the following options, bitwise-OR-ed
      * together: PARSE_VARIABLES, PARSE_ESCAPES, SKIP_WHITESPACE.
      */
     public void skipIgnored(int options) {
         if ((options & SKIP_WHITESPACE) != 0) {
             for (;;) {
                 int a = _current();
                 if (!PatternProps.isWhiteSpace(a)) break;
                 _advance(UTF16.getCharCount(a));
             }
         }
     }

     /**
      * Returns a string containing the remainder of the characters to be
      * returned by this iterator, without any option processing.  If the
      * iterator is currently within a variable expansion, this will only
      * extend to the end of the variable expansion.
      * This method, together with getCurrentBufferPos() (which replace the former lookahead()),
      * is provided so that iterators may interoperate with string-based APIs. The typical
      * sequence of calls is to call skipIgnored(), then call these methods, then
      * parse that substring, then call jumpahead() to
      * resynchronize the iterator.
      * @return a string containing the characters to be returned by future
      * calls to next()
      */
     public String getCurrentBuffer() {
         if (buf != null) {
             return buf;
         } else {
             return text;
         }
     }

     public int getCurrentBufferPos() {
         if (buf != null) {
             return bufPos;
         } else {
             return pos.getIndex();
         }
     }

     /**
      * Advances the position by the given number of 16-bit code units.
      * This is useful in conjunction with getCurrentBuffer()+getCurrentBufferPos()
      * (formerly lookahead()).
      * @param count the number of 16-bit code units to jump over
      */
     public void jumpahead(int count) {
         if (count < 0) {
             throw new IllegalArgumentException();
         }
         if (buf != null) {
             bufPos += count;
             if (bufPos > buf.length()) {
                 throw new IllegalArgumentException();
             }
             if (bufPos == buf.length()) {
                 buf = null;
             }
         } else {
             int i = pos.getIndex() + count;
             pos.setIndex(i);
             if (i > text.length()) {
                 throw new IllegalArgumentException();
             }
         }
     }

     /**
      * Returns a string representation of this object, consisting of the
      * characters being iterated, with a '|' marking the current position.
      * Position within an expanded variable is <em>not</em> indicated.
      * @return a string representation of this object
      */
     @Override
     public String toString() {
         int b = pos.getIndex();
         return text.substring(0, b) + '|' + text.substring(b);
     }

     /**
      * Returns the current 32-bit code point without parsing escapes, parsing
      * variables, or skipping whitespace.
      * @return the current 32-bit code point
      */
     private int _current() {
         if (buf != null) {
             return UTF16.charAt(buf, bufPos);
         } else {
             int i = pos.getIndex();
             return (i < text.length()) ? UTF16.charAt(text, i) : DONE;
         }
     }

     /**
      * Advances the position by the given amount.
      * @param count the number of 16-bit code units to advance past
      */
     private void _advance(int count) {
         if (buf != null) {
             bufPos += count;
             if (bufPos == buf.length()) {
                 buf = null;
             }
         } else {
             pos.setIndex(pos.getIndex() + count);
             if (pos.getIndex() > text.length()) {
                 pos.setIndex(text.length());
             }
         }
     }
 }
	/* GENERATED SOURCE. DO NOT MODIFY. */
	// © 2016 and later: Unicode, Inc. and others.
	// License & terms of use: http://www.unicode.org/copyright.html
	/*
	**********************************************************************
	* Copyright (c) 2003-2011, International Business Machines
	* Corporation and others. All Rights Reserved.
	**********************************************************************
	* Author: Alan Liu
	* Created: September 23 2003
	* Since: ICU 2.8
	**********************************************************************
	*/
	package android.icu.impl;

	import java.text.ParsePosition;

	import android.icu.text.SymbolTable;
	import android.icu.text.UTF16;

	/**
	* An iterator that returns 32-bit code points. This class is deliberately
	* <em>not</em> related to any of the JDK or ICU4J character iterator classes
	* in order to minimize complexity.
	* @author Alan Liu
	* @hide Only a subset of ICU is exposed in Android
	*/
	public class RuleCharacterIterator {

	// TODO: Ideas for later. (Do not implement if not needed, lest the
	// code coverage numbers go down due to unused methods.)
	// 1. Add a copy constructor, equals() method, clone() method.
	// 2. Rather than return DONE, throw an exception if the end
	// is reached -- this is an alternate usage model, probably not useful.
	// 3. Return isEscaped from next(). If this happens,
	// don't keep an isEscaped member variable.

	/**
	* Text being iterated.
	*/
	private String text;

	/**
	* Position of iterator.
	*/
	private ParsePosition pos;

	/**
	* Symbol table used to parse and dereference variables. May be null.
	*/
	private SymbolTable sym;

	/**
	* Current variable expansion, or null if none.
	*/
	private String buf;

	/**
	* Position within buf[]. Meaningless if buf == null.
	*/
	private int bufPos;

	/**
	* Flag indicating whether the last character was parsed from an escape.
	*/
	private boolean isEscaped;

	/**
	* Value returned when there are no more characters to iterate.
	*/
	public static final int DONE = -1;

	/**
	* Bitmask option to enable parsing of variable names. If (options &
	* PARSE_VARIABLES) != 0, then an embedded variable will be expanded to
	* its value. Variables are parsed using the SymbolTable API.
	*/
	public static final int PARSE_VARIABLES = 1;

	/**
	* Bitmask option to enable parsing of escape sequences. If (options &
	* PARSE_ESCAPES) != 0, then an embedded escape sequence will be expanded
	* to its value. Escapes are parsed using Utility.unescapeAndLengthAt().
	*/
	public static final int PARSE_ESCAPES = 2;

	/**
	* Bitmask option to enable skipping of whitespace. If (options &
	* SKIP_WHITESPACE) != 0, then Unicode Pattern_White_Space characters will be silently
	* skipped, as if they were not present in the input.
	*/
	public static final int SKIP_WHITESPACE = 4;

	/** For use with {@link #getPos(Position)} & {@link #setPos(Position)}.
	* @hide Only a subset of ICU is exposed in Android*/
	public static final class Position {
	private String buf;
	private int bufPos;
	private int posIndex;
	};

	/**
	* Constructs an iterator over the given text, starting at the given
	* position.
	* @param text the text to be iterated
	* @param sym the symbol table, or null if there is none. If sym is null,
	* then variables will not be dereferenced, even if the PARSE_VARIABLES
	* option is set.
	* @param pos upon input, the index of the next character to return. If a
	* variable has been dereferenced, then pos will <em>not</em> increment as
	* characters of the variable value are iterated.
	*/
	public RuleCharacterIterator(String text, SymbolTable sym,
	ParsePosition pos) {
	if (text == null \|\| pos.getIndex() > text.length()) {
	throw new IllegalArgumentException();
	}
	this.text = text;
	this.sym = sym;
	this.pos = pos;
	buf = null;
	}

	/**
	* Returns true if this iterator has no more characters to return.
	*/
	public boolean atEnd() {
	return buf == null && pos.getIndex() == text.length();
	}

	/**
	* Returns the next character using the given options, or DONE if there
	* are no more characters, and advance the position to the next
	* character.
	* @param options one or more of the following options, bitwise-OR-ed
	* together: PARSE_VARIABLES, PARSE_ESCAPES, SKIP_WHITESPACE.
	* @return the current 32-bit code point, or DONE
	*/
	public int next(int options) {
	int c = DONE;
	isEscaped = false;

	for (;;) {
	c = _current();
	_advance(UTF16.getCharCount(c));

	if (c == SymbolTable.SYMBOL_REF && buf == null &&
	(options & PARSE_VARIABLES) != 0 && sym != null) {
	String name = sym.parseReference(text, pos, text.length());
	// If name == null there was an isolated SYMBOL_REF;
	// return it. Caller must be prepared for this.
	if (name == null) {
	break;
	}
	bufPos = 0;
	char[] chars = sym.lookup(name);
	if (chars == null) {
	buf = null;
	throw new IllegalArgumentException(
	"Undefined variable: " + name);
	}
	// Handle empty variable value
	if (chars.length == 0) {
	buf = null;
	}
	buf = new String(chars);
	continue;
	}

	if ((options & SKIP_WHITESPACE) != 0 &&
	PatternProps.isWhiteSpace(c)) {
	continue;
	}

	if (c == '\\' && (options & PARSE_ESCAPES) != 0) {
	int cpAndLength = Utility.unescapeAndLengthAt(
	getCurrentBuffer(), getCurrentBufferPos());
	if (cpAndLength < 0) {
	throw new IllegalArgumentException("Invalid escape");
	}
	c = Utility.cpFromCodePointAndLength(cpAndLength);
	jumpahead(Utility.lengthFromCodePointAndLength(cpAndLength));
	isEscaped = true;
	}

	break;
	}

	return c;
	}

	/**
	* Returns true if the last character returned by next() was
	* escaped. This will only be the case if the option passed in to
	* next() included PARSE_ESCAPED and the next character was an
	* escape sequence.
	*/
	public boolean isEscaped() {
	return isEscaped;
	}

	/**
	* Returns true if this iterator is currently within a variable expansion.
	*/
	public boolean inVariable() {
	return buf != null;
	}

	/**
	* Returns an object which, when later passed to setPos(), will
	* restore this iterator's position. Usage idiom:
	*
	* RuleCharacterIterator iterator = ...;
	* Position pos = iterator.getPos(null); // allocate position object
	* for (;;) {
	* pos = iterator.getPos(pos); // reuse position object
	* int c = iterator.next(...);
	* ...
	* }
	* iterator.setPos(pos);
	*
	* @param p a position object previously returned by getPos(),
	* or null. If not null, it will be updated and returned. If
	* null, a new position object will be allocated and returned.
	* @return a position object which may be passed to setPos(),
	* either `p,' or if `p' == null, a newly-allocated object
	*/
	public Position getPos(Position p) {
	if (p == null) {
	p = new Position();
	}
	p.buf = buf;
	p.bufPos = bufPos;
	p.posIndex = pos.getIndex();
	return p;
	}

	/**
	* Restores this iterator to the position it had when getPos()
	* returned the given object.
	* @param p a position object previously returned by getPos()
	*/
	public void setPos(Position p) {
	buf = p.buf;
	pos.setIndex(p.posIndex);
	bufPos = p.bufPos;
	}

	/**
	* Skips ahead past any ignored characters, as indicated by the given
	* options. This is useful in conjunction with the lookahead() method.
	*
	* Currently, this only has an effect for SKIP_WHITESPACE.
	* @param options one or more of the following options, bitwise-OR-ed
	* together: PARSE_VARIABLES, PARSE_ESCAPES, SKIP_WHITESPACE.
	*/
	public void skipIgnored(int options) {
	if ((options & SKIP_WHITESPACE) != 0) {
	for (;;) {
	int a = _current();
	if (!PatternProps.isWhiteSpace(a)) break;
	_advance(UTF16.getCharCount(a));
	}
	}
	}

	/**
	* Returns a string containing the remainder of the characters to be
	* returned by this iterator, without any option processing. If the
	* iterator is currently within a variable expansion, this will only
	* extend to the end of the variable expansion.
	* This method, together with getCurrentBufferPos() (which replace the former lookahead()),
	* is provided so that iterators may interoperate with string-based APIs. The typical
	* sequence of calls is to call skipIgnored(), then call these methods, then
	* parse that substring, then call jumpahead() to
	* resynchronize the iterator.
	* @return a string containing the characters to be returned by future
	* calls to next()
	*/
	public String getCurrentBuffer() {
	if (buf != null) {
	return buf;
	} else {
	return text;
	}
	}

	public int getCurrentBufferPos() {
	if (buf != null) {
	return bufPos;
	} else {
	return pos.getIndex();
	}
	}

	/**
	* Advances the position by the given number of 16-bit code units.
	* This is useful in conjunction with getCurrentBuffer()+getCurrentBufferPos()
	* (formerly lookahead()).
	* @param count the number of 16-bit code units to jump over
	*/
	public void jumpahead(int count) {
	if (count < 0) {
	throw new IllegalArgumentException();
	}
	if (buf != null) {
	bufPos += count;
	if (bufPos > buf.length()) {
	throw new IllegalArgumentException();
	}
	if (bufPos == buf.length()) {
	buf = null;
	}
	} else {
	int i = pos.getIndex() + count;
	pos.setIndex(i);
	if (i > text.length()) {
	throw new IllegalArgumentException();
	}
	}
	}

	/**
	* Returns a string representation of this object, consisting of the
	* characters being iterated, with a '\|' marking the current position.
	* Position within an expanded variable is <em>not</em> indicated.
	* @return a string representation of this object
	*/
	@Override
	public String toString() {
	int b = pos.getIndex();
	return text.substring(0, b) + '\|' + text.substring(b);
	}

	/**
	* Returns the current 32-bit code point without parsing escapes, parsing
	* variables, or skipping whitespace.
	* @return the current 32-bit code point
	*/
	private int _current() {
	if (buf != null) {
	return UTF16.charAt(buf, bufPos);
	} else {
	int i = pos.getIndex();
	return (i < text.length()) ? UTF16.charAt(text, i) : DONE;
	}
	}

	/**
	* Advances the position by the given amount.
	* @param count the number of 16-bit code units to advance past
	*/
	private void _advance(int count) {
	if (buf != null) {
	bufPos += count;
	if (bufPos == buf.length()) {
	buf = null;
	}
	} else {
	pos.setIndex(pos.getIndex() + count);
	if (pos.getIndex() > text.length()) {
	pos.setIndex(text.length());
	}
	}
	}
	}