diff options
Diffstat (limited to 'BJC-Utils2/src/main/java/bjc/utils/funcutils')
3 files changed, 89 insertions, 15 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/FunctionalFileVisitor.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/FunctionalFileVisitor.java index 4310416..db6c43b 100644 --- a/BJC-Utils2/src/main/java/bjc/utils/funcutils/FunctionalFileVisitor.java +++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/FunctionalFileVisitor.java @@ -7,6 +7,9 @@ import java.nio.file.SimpleFileVisitor; import java.nio.file.attribute.BasicFileAttributes; import java.util.function.BiPredicate; +/* + * Functional implementation of a file visitor. + */ final class FunctionalFileVisitor extends SimpleFileVisitor<Path> { private final BiPredicate<Path, BasicFileAttributes> predicate; private final BiPredicate<Path, BasicFileAttributes> action; diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/ListUtils.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/ListUtils.java index 52a2437..c0daa1e 100644 --- a/BJC-Utils2/src/main/java/bjc/utils/funcutils/ListUtils.java +++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/ListUtils.java @@ -95,13 +95,19 @@ public class ListUtils { E element = null; for (final int index = 0; itr.hasNext(); element = itr.next()) { - // n - m + /* + * n - m + */ final int winningChance = number - selected.getSize(); - // N - t + /* + * N - t + */ final int totalChance = total - (index - 1); - // Probability of selecting the t+1'th element + /* + * Probability of selecting the t+1'th element + */ if (NumberUtils.isProbable(winningChance, totalChance, rng)) { selected.add(element); } @@ -185,17 +191,20 @@ public class ListUtils { && !rejected.isEmpty(); numberOfIterations++) { input.forEach(it); - if (rejected.isEmpty()) // Nothing was rejected, so - // we're - // done + if (rejected.isEmpty()) { + /* + * Nothing was rejected, so we're done + */ return returned; + } } - throw new IllegalArgumentException("Heuristic (more than " + MAX_NTRIESPART - + " iterations of partitioning) detected unpartitionable list " + input.toString() - + "\nThe following elements were not partitioned: " + rejected.toString() - + "\nCurrent group in formation: " + it.currentPartition.toString() - + "\nPreviously formed groups: " + returned.toString()); + + final String fmt = "Heuristic (more than %d iterations of partitioning) detected an unpartitionable list. (%s)\nThe following elements were not partitioned: %s\nCurrent group in formation: %s\nPreviously formed groups: %s\n"; + + final String msg = String.format(fmt, MAX_NTRIESPART, input.toString(), rejected.toString(), it.currentPartition.toString(), returned.toString()); + + throw new IllegalArgumentException(msg); } /** @@ -250,7 +259,9 @@ public class ListUtils { } if (count % size != 0) { - // We need to pad + /* + * We need to pad + */ int needed = count % size; int threshold = 0; @@ -269,9 +280,13 @@ public class ListUtils { } } - if (threshold > MAX_NTRIESPART) - throw new IllegalArgumentException("Heuristic (more than " + MAX_NTRIESPART - + " iterations of attempting to pad) detected unpaddable list "); + if (threshold > MAX_NTRIESPART) { + final String fmt = "Heuristic (more than %d iterations of attempting to pad) detected an unpaddable list. (%s)\nPartially padded list: %S"; + + final String msg = String.format(fmt, MAX_NTRIESPART, list.toString(), returned.toString()); + + throw new IllegalArgumentException(msg); + } } return returned; diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/TreeUtils.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/TreeUtils.java new file mode 100644 index 0000000..dcd5738 --- /dev/null +++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/TreeUtils.java @@ -0,0 +1,56 @@ +package bjc.utils.funcutils; + +import java.util.LinkedList; +import java.util.function.Predicate; + +import bjc.utils.data.ITree; +import bjc.utils.funcdata.FunctionalList; +import bjc.utils.funcdata.IList; + +/** + * Implements various utilities for trees. + * + * @author Benjamin Culkin + */ +public class TreeUtils { + /* + * Convert a tree into a list of outline nodes that match a certain + * path. + */ + public static <T> IList<IList<T>> outlineTree(ITree<T> tre, Predicate<T> leafMarker) { + IList<IList<T>> paths = new FunctionalList<>(); + + LinkedList<T> path = new LinkedList<>(); + path.add(tre.getHead()); + + tre.doForChildren((child) -> findPath(child, path, leafMarker, paths)); + + return paths; + } + + private static <T> void findPath(ITree<T> subtree, LinkedList<T> path, Predicate<T> leafMarker, IList<IList<T>> paths) { + if(subtree.getChildrenCount() == 0 && leafMarker.test(subtree.getHead())) { + /* + * We're at a matching leaf node. Add it. + */ + IList<T> finalPath = new FunctionalList<>(); + + for(T ePath : path) { + finalPath.add(ePath); + } + + finalPath.add(subtree.getHead()); + + paths.add(finalPath); + } else { + /* + * Check the children of this node. + */ + path.add(subtree.getHead()); + + subtree.doForChildren((child) -> findPath(child, path, leafMarker, paths)); + + path.removeLast(); + } + } +} |