cdc.io.data.paths.SPath Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of cdc-io-data Show documentation
The newest version!
package cdc.io.data.paths;

import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.function.Predicate;

import cdc.io.data.Element;
import cdc.io.data.Parent;
import cdc.util.lang.Checks;
import cdc.util.lang.CollectionUtils;

/**
 * Simple path.
 * 
 * It must have the form: {@code (part/)*part} or {@code (part(/part)*)?@part}
 *
 * @author Damien Carbonne
 *
 */
public final class SPath {
    private final List parts;
    private final boolean isAttribute;

    public SPath(String text) {
        // Index of the attribute separator
        final int index = text.lastIndexOf('@');
        this.isAttribute = index >= 0;

        final String[] tmp;
        if (index == 0) {
            // Only an attribute
            tmp = new String[0];
        } else if (index > 0) {
            // Elements and attribute
            tmp = text.substring(0, index).split("/");
        } else {
            // No attribute
            tmp = text.split("/");
        }
        final List l = CollectionUtils.toList(tmp);
        if (isAttribute) {
            final String last = text.substring(index + 1);
            Checks.isFalse(last.contains("/"), "An attribute name can not contain '/'");
            l.add(last);
        }
        this.parts = Collections.unmodifiableList(l);
    }

    public List getParts() {
        return parts;
    }

    public boolean isAttribute() {
        return isAttribute;
    }

    public boolean isElement() {
        return !isAttribute;
    }

    @Override
    public String toString() {
        final StringBuilder builder = new StringBuilder();
        final int size = parts.size();
        for (int index = 0; index < size; index++) {
            if (index > 0) {
                if (index == size - 1 && isAttribute) {
                    builder.append('@');
                } else {
                    builder.append('/');
                }
            }
            builder.append(parts.get(index));
        }
        return builder.toString();
    }

    private boolean matches(Parent parent,
                            String name,
                            boolean attribute) {
        // System.out.println(this + ".matches(" + (parent == null ? "null" : parent.getQName()) + ", " + name + ") " + getParts());
        if (attribute != isAttribute || parts.isEmpty()) {
            // System.out.println("1");
            return false;
        } else {
            if (Objects.equals(name, parts.get(parts.size() - 1))) {
                // System.out.println("Last part match");
                Parent p = parent;
                for (int index = parts.size() - 2; index >= 0; index--) {
                    // System.out.println("Check: " + p.getQName());
                    if (p instanceof Element) {
                        final Element e = (Element) p;
                        if (e.getName().equals(parts.get(index))) {
                            // System.out.println("part match: " + e.getName());
                            p = e.getParent();
                        } else {
                            return false;
                        }
                    } else {
                        return false;
                    }
                }
                return true;
            } else {
                // System.out.println("2");
                return false;
            }
        }
    }

    public boolean matchesElement(Parent parent) {
        if (parent instanceof Element) {
            final Element element = (Element) parent;
            return matchesElement(element.getParent(), element.getName());
        } else {
            return false;
        }
    }

    /**
     * Returns {@code true} if this SPath matches an element.
     *
     * @param parent The parent element.
     * @param name The name of the child element.
     * @return {@code true} if this SPath matches {@code child} under {@code parent}.
     */
    public boolean matchesElement(Parent parent,
                                  String name) {
        return matches(parent, name, false);
    }

    /**
     * Returns {@code true} if this SPath matches an attribute in an element.
     *
     * @param parent The element.
     * @param name The attribute name.
     * @return {@code true} if this SPath matches an attribute named {@code name} in {@code parent}.
     */
    public boolean matchesAttribute(Element parent,
                                    String name) {
        return matches(parent, name, true);
    }

    public static Predicate toStandardPredicate(Collection paths) {
        Checks.isNotNull(paths, "paths");
        return (Element element) -> {
            for (final SPath path : paths) {
                if (path.matchesElement(element)) {
                    return true;
                }
            }
            return false;
        };
    }

    @Override
    public int hashCode() {
        return toString().hashCode();
    }

    @Override
    public boolean equals(Object object) {
        if (this == object) {
            return true;
        }
        if (!(object instanceof SPath)) {
            return false;
        }
        final SPath other = (SPath) object;
        return this.isAttribute == other.isAttribute
                && this.parts.equals(other.parts);
    }
}