*/
package org.opendaylight.yangtools.yang.model.api;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkState;
+import static java.util.Objects.requireNonNull;
+import com.google.common.base.MoreObjects;
+import com.google.common.base.MoreObjects.ToStringHelper;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.UnmodifiableIterator;
+import java.util.Arrays;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.Objects;
+import org.eclipse.jdt.annotation.NonNull;
+import org.opendaylight.yangtools.concepts.Immutable;
import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier;
+import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
+import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Descendant;
/**
- *
* Represents unique path to the every node inside the module.
- *
*/
-public class SchemaPath {
- private final int hashBooleanTrue = 1231;
- private final int hashBooleanFalse = 1237;
+public abstract class SchemaPath implements Immutable {
+
+ /**
+ * An absolute SchemaPath.
+ */
+ private static final class AbsoluteSchemaPath extends SchemaPath {
+ private AbsoluteSchemaPath(final SchemaPath parent, final QName qname) {
+ super(parent, qname);
+ }
+
+ @Override
+ public boolean isAbsolute() {
+ return true;
+ }
+
+ @Override
+ public AbsoluteSchemaPath createChild(final QName element) {
+ return new AbsoluteSchemaPath(this, requireNonNull(element));
+ }
+ }
+
+ /**
+ * A relative SchemaPath.
+ */
+ private static final class RelativeSchemaPath extends SchemaPath {
+ private RelativeSchemaPath(final SchemaPath parent, final QName qname) {
+ super(parent, qname);
+ }
+
+ @Override
+ public boolean isAbsolute() {
+ return false;
+ }
+
+ @Override
+ public RelativeSchemaPath createChild(final QName element) {
+ return new RelativeSchemaPath(this, requireNonNull(element));
+ }
+ }
+
+ /**
+ * Shared instance of the conceptual root schema node.
+ */
+ public static final @NonNull SchemaPath ROOT = new AbsoluteSchemaPath(null, null);
+
+ /**
+ * Shared instance of the "same" relative schema node.
+ */
+ public static final @NonNull SchemaPath SAME = new RelativeSchemaPath(null, null);
/**
- * List of QName instances which represents complete path to the node.
+ * Parent path.
*/
- private final List<QName> path;
+ private final SchemaPath parent;
/**
- * Boolean value which represents type of schema path (relative or
- * absolute).
+ * This component.
*/
- private final boolean absolute;
+ private final QName qname;
+
+ /**
+ * Cached hash code. We can use this since we are immutable.
+ */
+ private final int hash;
+
+ SchemaPath(final SchemaPath parent, final QName qname) {
+ this.parent = parent;
+ this.qname = qname;
+
+ int tmp = Objects.hashCode(parent);
+ if (qname != null) {
+ tmp = tmp * 31 + qname.hashCode();
+ }
+
+ hash = tmp;
+ }
/**
* Constructs new instance of this class with the concrete path.
- *
+ *
* @param path
* list of QName instances which specifies exact path to the
* module node
* @param absolute
* boolean value which specifies if the path is absolute or
* relative
+ *
+ * @return A SchemaPath instance.
+ */
+ public static @NonNull SchemaPath create(final Iterable<QName> path, final boolean absolute) {
+ return (absolute ? ROOT : SAME).createChild(path);
+ }
+
+ /**
+ * Constructs new instance of this class with the concrete path.
+ *
+ * @param absolute
+ * boolean value which specifies if the path is absolute or
+ * relative
+ * @param element
+ * a single QName which specifies exact path to the
+ * module node
+ *
+ * @return A SchemaPath instance.
+ */
+ public static @NonNull SchemaPath create(final boolean absolute, final QName element) {
+ return (absolute ? ROOT : SAME).createChild(element);
+ }
+
+ /**
+ * Constructs new instance of this class with the concrete path.
+ *
+ * @param absolute
+ * boolean value which specifies if the path is absolute or
+ * relative
+ * @param path
+ * one or more QName instances which specifies exact path to the
+ * module node
+ *
+ * @return A SchemaPath instance.
+ */
+ public static @NonNull SchemaPath create(final boolean absolute, final QName... path) {
+ return create(Arrays.asList(path), absolute);
+ }
+
+ /**
+ * Create a child path based on concatenation of this path and a relative path.
+ *
+ * @param relative Relative path
+ * @return A new child path
+ */
+ public @NonNull SchemaPath createChild(final Iterable<QName> relative) {
+ if (Iterables.isEmpty(relative)) {
+ return this;
+ }
+
+ SchemaPath parentPath = this;
+ for (QName item : relative) {
+ parentPath = parentPath.createChild(item);
+ }
+
+ return parentPath;
+ }
+
+ /**
+ * Create a child path based on concatenation of this path and a relative path.
+ *
+ * @param relative Relative SchemaPath
+ * @return A new child path
+ */
+ public @NonNull SchemaPath createChild(final SchemaPath relative) {
+ checkArgument(!relative.isAbsolute(), "Child creation requires relative path");
+ return createChild(relative.getPathFromRoot());
+ }
+
+ /**
+ * Create a child path based on concatenation of this path and an additional path element.
+ *
+ * @param element Relative SchemaPath elements
+ * @return A new child path
+ */
+ public abstract @NonNull SchemaPath createChild(QName element);
+
+ /**
+ * Create a child path based on concatenation of this path and additional
+ * path elements.
+ *
+ * @param elements Relative SchemaPath elements
+ * @return A new child path
+ */
+ public @NonNull SchemaPath createChild(final QName... elements) {
+ return createChild(Arrays.asList(elements));
+ }
+
+ /**
+ * Returns the list of nodes which need to be traversed to get from the
+ * starting point (root for absolute SchemaPaths) to the node represented
+ * by this object.
+ *
+ * @return list of <code>qname</code> instances which represents
+ * path from the root to the schema node.
+ */
+ public List<QName> getPathFromRoot() {
+ if (qname == null) {
+ return ImmutableList.of();
+ }
+ return parent == null ? ImmutableList.of(qname) : new PathFromRoot(this);
+ }
+
+ /**
+ * Returns the list of nodes which need to be traversed to get from this
+ * node to the starting point (root for absolute SchemaPaths).
+ *
+ * @return list of <code>qname</code> instances which represents
+ * path from the schema node towards the root.
+ */
+ public Iterable<QName> getPathTowardsRoot() {
+ return () -> new UnmodifiableIterator<>() {
+ private SchemaPath current = SchemaPath.this;
+
+ @Override
+ public boolean hasNext() {
+ return current.parent != null;
+ }
+
+ @Override
+ public QName next() {
+ if (current.parent != null) {
+ final QName ret = current.qname;
+ current = current.parent;
+ return ret;
+ }
+
+ throw new NoSuchElementException("No more elements available");
+ }
+ };
+ }
+
+ /**
+ * Returns the immediate parent SchemaPath.
+ *
+ * @return Parent path, null if this SchemaPath is already toplevel.
*/
- public SchemaPath(final List<QName> path, boolean absolute) {
- this.path = Collections.unmodifiableList(new ArrayList<QName>(path));
- this.absolute = absolute;
+ public SchemaPath getParent() {
+ return parent;
}
/**
- * Returns the complete path to schema node.
- *
- * @return list of <code>QName</code> instances which represents complete
- * path to schema node
+ * Get the last component of this path.
+ *
+ * @return The last component of this path.
*/
- public List<QName> getPath() {
- return path;
+ public final QName getLastComponent() {
+ return qname;
}
/**
* Describes whether schema path is|isn't absolute.
- *
+ *
* @return boolean value which is <code>true</code> if schema path is
* absolute.
*/
- public boolean isAbsolute() {
- return absolute;
+ public abstract boolean isAbsolute();
+
+ /**
+ * Return this path as a {@link SchemaNodeIdentifier}.
+ *
+ * @return A SchemaNodeIdentifier.
+ * @throws IllegalStateException if this path is empty
+ */
+ public final SchemaNodeIdentifier asSchemaNodeIdentifier() {
+ checkState(qname != null, "Cannot convert empty %s", this);
+ final List<QName> path = getPathFromRoot();
+ return isAbsolute() ? Absolute.of(path) : Descendant.of(path);
+ }
+
+ /**
+ * Return this path as an {@link Absolute} SchemaNodeIdentifier.
+ *
+ * @return An SchemaNodeIdentifier.
+ * @throws IllegalStateException if this path is empty or is not absolute.
+ */
+ public final Absolute asAbsolute() {
+ final SchemaNodeIdentifier ret = asSchemaNodeIdentifier();
+ if (ret instanceof Absolute) {
+ return (Absolute) ret;
+ }
+ throw new IllegalStateException("Path " + this + " is relative");
+ }
+
+ /**
+ * Return this path as an {@link Descendant} SchemaNodeIdentifier.
+ *
+ * @return An SchemaNodeIdentifier.
+ * @throws IllegalStateException if this path is empty or is not relative.
+ */
+ public final Descendant asDescendant() {
+ final SchemaNodeIdentifier ret = asSchemaNodeIdentifier();
+ if (ret instanceof Descendant) {
+ return (Descendant) ret;
+ }
+ throw new IllegalStateException("Path " + this + " is absolute");
}
@Override
- public int hashCode() {
- final int prime = 31;
- int result = 1;
- result = prime * result + (absolute ? hashBooleanTrue : hashBooleanFalse);
- result = prime * result + ((path == null) ? 0 : path.hashCode());
- return result;
+ public final int hashCode() {
+ return hash;
}
@Override
- public boolean equals(Object obj) {
+ public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (getClass() != obj.getClass()) {
return false;
}
- SchemaPath other = (SchemaPath) obj;
- if (absolute != other.absolute) {
- return false;
- }
- if (path == null) {
- if (other.path != null) {
- return false;
- }
- } else if (!path.equals(other.path)) {
- return false;
- }
- return true;
+ final SchemaPath other = (SchemaPath) obj;
+ return Objects.equals(qname, other.qname) && Objects.equals(parent, other.parent);
}
@Override
- public String toString() {
- StringBuilder builder = new StringBuilder();
- builder.append("SchemaPath [path=");
- builder.append(path);
- builder.append(", absolute=");
- builder.append(absolute);
- builder.append("]");
- return builder.toString();
+ public final String toString() {
+ return addToStringAttributes(MoreObjects.toStringHelper(this)).toString();
+ }
+
+ protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
+ return toStringHelper.add("path", getPathFromRoot());
}
}
Code Review / yangtools.git / blobdiff