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Diffstat (limited to 'libjava/gnu/gcj/text/SentenceBreakIterator.java')
| -rw-r--r-- | libjava/gnu/gcj/text/SentenceBreakIterator.java | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/libjava/gnu/gcj/text/SentenceBreakIterator.java b/libjava/gnu/gcj/text/SentenceBreakIterator.java new file mode 100644 index 00000000000..8668087b23f --- /dev/null +++ b/libjava/gnu/gcj/text/SentenceBreakIterator.java @@ -0,0 +1,226 @@ +// Default sentence BreakIterator. + +/* Copyright (C) 1999 Cygnus Solutions + + This file is part of libgcj. + +This software is copyrighted work licensed under the terms of the +Libgcj License. Please consult the file "LIBGCJ_LICENSE" for +details. */ + +package gnu.gcj.text; + +import java.text.BreakIterator; +import java.text.CharacterIterator; + +/** + * @author Tom Tromey <tromey@cygnus.com> + * @date March 23, 1999 + * Written using The Unicode Standard, Version 2.0. + */ + +public class SentenceBreakIterator extends BaseBreakIterator +{ + public Object clone () + { + return new SentenceBreakIterator (this); + } + + public SentenceBreakIterator () + { + iter = null; + } + + private SentenceBreakIterator (SentenceBreakIterator other) + { + iter = (CharacterIterator) other.iter.clone(); + } + + public int next () + { + int end = iter.getEndIndex(); + if (iter.getIndex() == end) + return DONE; + + while (iter.getIndex() < end) + { + char c = iter.current(); + if (c == CharacterIterator.DONE) + break; + int type = Character.getType(c); + + char n = iter.next(); + if (n == CharacterIterator.DONE) + break; + + // Always break after paragraph separator. + if (type == Character.PARAGRAPH_SEPARATOR) + break; + + if (c == '!' || c == '?') + { + // Skip close punctuation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.END_PUNCTUATION) + n = iter.next(); + // Skip spaces. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.SPACE_SEPARATOR) + n = iter.next(); + // Skip optional paragraph separator. + if (n != CharacterIterator.DONE + && Character.getType(n) == Character.PARAGRAPH_SEPARATOR) + n = iter.next(); + + // There's always a break somewhere after `!' or `?'. + break; + } + + if (c == '.') + { + int save = iter.getIndex(); + // Skip close punctuation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.END_PUNCTUATION) + n = iter.next(); + // Skip spaces. We keep count because we need at least + // one for this period to represent a terminator. + int spcount = 0; + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.SPACE_SEPARATOR) + { + n = iter.next(); + ++spcount; + } + if (spcount > 0) + { + int save2 = iter.getIndex(); + // Skip over open puncutation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.START_PUNCTUATION) + n = iter.next(); + // Next character must not be lower case. + if (n == CharacterIterator.DONE + || ! Character.isLowerCase(n)) + { + iter.setIndex(save2); + break; + } + } + iter.setIndex(save); + } + } + + return iter.getIndex(); + } + + private final int previous_internal () + { + int start = iter.getBeginIndex(); + if (iter.getIndex() == start) + return DONE; + + while (iter.getIndex() >= start) + { + char c = iter.previous(); + if (c == CharacterIterator.DONE) + break; + + char n = iter.previous(); + if (n == CharacterIterator.DONE) + break; + iter.next(); + int nt = Character.getType(n); + + if (! Character.isLowerCase(c) + && (nt == Character.START_PUNCTUATION + || nt == Character.SPACE_SEPARATOR)) + { + int save = iter.getIndex(); + int save_nt = nt; + char save_n = n; + // Skip open punctuation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.START_PUNCTUATION) + n = iter.previous(); + if (n == CharacterIterator.DONE) + break; + if (Character.getType(n) == Character.SPACE_SEPARATOR) + { + // Must have at least once space after the `.'. + int save2 = iter.getIndex(); + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.SPACE_SEPARATOR) + n = iter.previous(); + // Skip close punctuation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.END_PUNCTUATION) + n = iter.previous(); + if (n == CharacterIterator.DONE || n == '.') + { + // Communicate location of actual end. + period = iter.getIndex(); + iter.setIndex(save2); + break; + } + } + iter.setIndex(save); + nt = save_nt; + n = save_n; + } + + if (nt == Character.PARAGRAPH_SEPARATOR) + { + // Communicate location of actual end. + period = iter.getIndex(); + break; + } + else if (nt == Character.SPACE_SEPARATOR + || nt == Character.END_PUNCTUATION) + { + int save = iter.getIndex(); + // Skip spaces. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.SPACE_SEPARATOR) + n = iter.previous(); + // Skip close punctuation. + while (n != CharacterIterator.DONE + && Character.getType(n) == Character.END_PUNCTUATION) + n = iter.previous(); + int here = iter.getIndex(); + iter.setIndex(save); + if (n == CharacterIterator.DONE || n == '!' || n == '?') + { + // Communicate location of actual end. + period = here; + break; + } + } + else if (n == '!' || n == '?') + { + // Communicate location of actual end. + period = iter.getIndex(); + break; + } + } + + return iter.getIndex(); + } + + public int previous () + { + // We want to skip over the first sentence end to the second one. + // However, at the end of the string we want the first end. + int here = iter.getIndex(); + period = here; + int first = previous_internal (); + if (here == iter.getEndIndex() || first == DONE) + return first; + iter.setIndex(period); + return previous_internal (); + } + + // This is used for communication between previous and + // previous_internal. + private int period; +} |