--- /dev/null
+package org.simantics.scl.ui.editor2.iterator;
+
+import java.text.CharacterIterator;
+
+import com.ibm.icu.text.BreakIterator;
+
+import org.eclipse.core.runtime.Assert;
+
+
+
+/**
+ * Breaks java text into word starts, also stops at line start and end. No
+ * direction dependency.
+ *
+ * @since 3.0
+ */
+public class JavaWordIterator extends BreakIterator {
+
+ /**
+ * The underlying java break iterator. It returns all breaks, including
+ * before and after every whitespace.
+ */
+ private JavaBreakIterator fIterator;
+ /** The current index for the stateful operations. */
+ private int fIndex;
+
+ /**
+ * Creates a new word iterator.
+ */
+ public JavaWordIterator() {
+ fIterator= new JavaBreakIterator();
+ first();
+ }
+
+ /*
+ * @see java.text.BreakIterator#first()
+ */
+ @Override
+ public int first() {
+ fIndex= fIterator.first();
+ return fIndex;
+ }
+
+ /*
+ * @see java.text.BreakIterator#last()
+ */
+ @Override
+ public int last() {
+ fIndex= fIterator.last();
+ return fIndex;
+ }
+
+ /*
+ * @see java.text.BreakIterator#next(int)
+ */
+ @Override
+ public int next(int n) {
+ int next= 0;
+ while (--n > 0 && next != DONE) {
+ next= next();
+ }
+ return next;
+ }
+
+ /*
+ * @see java.text.BreakIterator#next()
+ */
+ @Override
+ public int next() {
+ fIndex= following(fIndex);
+ return fIndex;
+ }
+
+ /*
+ * @see java.text.BreakIterator#previous()
+ */
+ @Override
+ public int previous() {
+ fIndex= preceding(fIndex);
+ return fIndex;
+ }
+
+
+ /*
+ * @see java.text.BreakIterator#preceding(int)
+ */
+ @Override
+ public int preceding(int offset) {
+ int first= fIterator.preceding(offset);
+ if (isWhitespace(first, offset)) {
+ int second= fIterator.preceding(first);
+ if (second != DONE && !isDelimiter(second, first))
+ return second;
+ }
+ return first;
+ }
+
+ /*
+ * @see java.text.BreakIterator#following(int)
+ */
+ @Override
+ public int following(int offset) {
+ int first= fIterator.following(offset);
+ if (eatFollowingWhitespace(offset, first)) {
+ int second= fIterator.following(first);
+ if (isWhitespace(first, second))
+ return second;
+ }
+ return first;
+ }
+
+ private boolean eatFollowingWhitespace(int offset, int exclusiveEnd) {
+ if (exclusiveEnd == DONE || offset == DONE)
+ return false;
+
+ if (isWhitespace(offset, exclusiveEnd))
+ return false;
+ if (isDelimiter(offset, exclusiveEnd))
+ return false;
+
+ return true;
+ }
+
+ /**
+ * Returns <code>true</code> if the given sequence into the underlying text
+ * represents a delimiter, <code>false</code> otherwise.
+ *
+ * @param offset the offset
+ * @param exclusiveEnd the end offset
+ * @return <code>true</code> if the given range is a delimiter
+ */
+ private boolean isDelimiter(int offset, int exclusiveEnd) {
+ if (exclusiveEnd == DONE || offset == DONE)
+ return false;
+
+ Assert.isTrue(offset >= 0);
+ Assert.isTrue(exclusiveEnd <= getText().getEndIndex());
+ Assert.isTrue(exclusiveEnd > offset);
+
+ CharSequence seq= fIterator.fText;
+
+ while (offset < exclusiveEnd) {
+ char ch= seq.charAt(offset);
+ if (ch != '\n' && ch != '\r')
+ return false;
+ offset++;
+ }
+
+ return true;
+ }
+
+ /**
+ * Returns <code>true</code> if the given sequence into the underlying text
+ * represents whitespace, but not a delimiter, <code>false</code> otherwise.
+ *
+ * @param offset the offset
+ * @param exclusiveEnd the end offset
+ * @return <code>true</code> if the given range is whitespace
+ */
+ private boolean isWhitespace(int offset, int exclusiveEnd) {
+ if (exclusiveEnd == DONE || offset == DONE)
+ return false;
+
+ Assert.isTrue(offset >= 0);
+ Assert.isTrue(exclusiveEnd <= getText().getEndIndex());
+ Assert.isTrue(exclusiveEnd > offset);
+
+ CharSequence seq= fIterator.fText;
+
+ while (offset < exclusiveEnd) {
+ char ch= seq.charAt(offset);
+ if (!Character.isWhitespace(ch))
+ return false;
+ if (ch == '\n' || ch == '\r')
+ return false;
+ offset++;
+ }
+
+ return true;
+ }
+
+ /*
+ * @see java.text.BreakIterator#current()
+ */
+ @Override
+ public int current() {
+ return fIndex;
+ }
+
+ /*
+ * @see java.text.BreakIterator#getText()
+ */
+ @Override
+ public CharacterIterator getText() {
+ return fIterator.getText();
+ }
+
+ /**
+ * Sets the text as <code>CharSequence</code>.
+ * @param newText the new text
+ */
+ public void setText(CharSequence newText) {
+ fIterator.setText(newText);
+ first();
+ }
+
+ /*
+ * @see java.text.BreakIterator#setText(java.text.CharacterIterator)
+ */
+ @Override
+ public void setText(CharacterIterator newText) {
+ fIterator.setText(newText);
+ first();
+ }
+
+ /*
+ * @see java.text.BreakIterator#setText(java.lang.String)
+ */
+ @Override
+ public void setText(String newText) {
+ setText((CharSequence) newText);
+ }
+
+}