Adding an initial API for the DomTree data structure.
Change-Id: I55da78c11f49c1e5843cfefbe0a5eed02c59498b
diff --git a/core/api/src/main/java/org/onosproject/store/primitives/DocumentTreeNode.java b/core/api/src/main/java/org/onosproject/store/primitives/DocumentTreeNode.java
new file mode 100644
index 0000000..dcc424b
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/primitives/DocumentTreeNode.java
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.primitives;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.Sets;
+import org.onosproject.store.service.DocumentPath;
+
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.Objects;
+import java.util.TreeSet;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * A tree node made for {@code DocumentTree}
+ * implementations that keeps records of its parent and children.
+ */
+public class DocumentTreeNode<V> {
+ private final DocumentPath key;
+ private V value;
+ private final TreeSet<DocumentTreeNode<V>> children =
+ Sets.newTreeSet(new Comparator<DocumentTreeNode<V>>() {
+ @Override
+ public int compare(DocumentTreeNode<V> o1,
+ DocumentTreeNode<V> o2) {
+ return o1.getKey().compareTo(o2.getKey());
+ }
+ });
+ private DocumentTreeNode parent;
+
+ public DocumentTreeNode(DocumentPath key, V value,
+ DocumentTreeNode parent) {
+ this.key = checkNotNull(key);
+ this.value = checkNotNull(value);
+ this.parent = parent;
+ }
+
+ /**
+ * Returns this objects key.
+ *
+ * @return the key
+ */
+ public DocumentPath getKey() {
+ return key;
+ }
+
+ /**
+ * Returns this objects value.
+ *
+ * @return the value
+ */
+ public V getValue() {
+ return value;
+ }
+
+ /**
+ * Sets this objects value.
+ *
+ * @param value the value to be set
+ */
+ public void setValue(V value) {
+ this.value = value;
+ }
+
+ /**
+ * Returns a collection of the children of this node.
+ *
+ * @return a sorted iterator for the children of this node.
+ */
+ public Iterator<DocumentTreeNode<V>> getChildren() {
+ return children.iterator();
+ }
+
+ /**
+ * Adds a child to this node.
+ *
+ * @param child the child node to be added
+ * @return true if the child set was modified as a result of this call,
+ * false otherwise
+ */
+ public boolean addChild(DocumentTreeNode<V> child) {
+ return children.add(child);
+ }
+
+ /**
+ * Removes a child from the children of this node.
+ *
+ * @param child the child node to be removed
+ * @return true if the child set was modified as a result of this call,
+ * false otherwise
+ */
+ public boolean removeChild(String child) {
+ return children.remove(child);
+ }
+
+ /**
+ * Returns the parent of this node.
+ *
+ * @return the parent node of this node, which may be null
+ */
+ public DocumentTreeNode<V> getParent() {
+ return parent;
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(this.key);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (obj instanceof DocumentTreeNode) {
+ DocumentTreeNode that = (DocumentTreeNode) obj;
+ if (this.parent.equals(that.parent)) {
+ if (this.children.size() == that.children.size()) {
+ for (DocumentTreeNode child : this.children) {
+ if (!that.children.contains(child)) {
+ return false;
+ }
+ }
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ @Override
+ public String toString() {
+ MoreObjects.ToStringHelper helper =
+ MoreObjects.toStringHelper(getClass())
+ .add("parent", this.parent)
+ .add("key", this.key)
+ .add("value", this.value);
+ for (DocumentTreeNode child : children) {
+ helper = helper.add("child", child.key);
+ }
+ return helper.toString();
+ }
+
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentException.java b/core/api/src/main/java/org/onosproject/store/service/DocumentException.java
new file mode 100644
index 0000000..d49b318
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentException.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+/**
+ * Exceptions for use by the {@code DocumentTree} and {@code DocumentPath}.
+ */
+public class DocumentException extends RuntimeException {
+ public DocumentException() {
+ super();
+ }
+
+ public DocumentException(String message) {
+ super(message);
+ }
+
+ public DocumentException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ public DocumentException(Throwable cause) {
+ super(cause);
+ }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
new file mode 100644
index 0000000..1147c22
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
@@ -0,0 +1,151 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A path class for identifying nodes within the {@code DocumentTree}.
+ *
+ * Note: indexing is ONE based so the root is the 1st level, to retrieve the
+ * root one should query level 1.
+ */
+public class DocumentPath implements Comparable {
+
+ private final ArrayList<String> tokens = Lists.newArrayList();
+
+ /**
+ * Private utility constructor for internal generation of partial paths only.
+ *
+ * @param path
+ */
+ private DocumentPath(List<String> path) {
+ Preconditions.checkNotNull(path);
+ this.tokens.addAll(path);
+ }
+
+ /**
+ * Constructor to generate new {@DocumentPath}, new paths must contain at
+ * least one name and string names may NOT contain any '.'s. If one field
+ * is null that field will be ignored.
+ *
+ * @throws IllegalDocumentNameException if both parameters are null or the string
+ * name contains an illegal character ('.')
+ * @param nodeName the name of the last level of this path
+ * @param parentPath the path representing the parents leading up to this
+ * node, in the case of the root this should be null
+ */
+ public DocumentPath(String nodeName, DocumentPath parentPath) {
+ if (nodeName.contains(".")) {
+ throw new IllegalDocumentNameException(
+ "Periods are not allowed in names.");
+ }
+ if (parentPath != null) {
+ tokens.addAll(parentPath.path());
+ }
+ if (nodeName != null) {
+ tokens.add(nodeName);
+ }
+ if (tokens.isEmpty()) {
+ throw new IllegalDocumentNameException("A document path must contain at" +
+ "least one non-null" +
+ "element.");
+ }
+ }
+
+ /**
+ * Returns a path from the root to the parent of this node, if this node is
+ * the root this call returns null.
+ *
+ * @return a {@code DocumentPath} representing a path to this paths parent,
+ * null if this a root path
+ */
+ public DocumentPath parent() {
+ if (tokens.size() <= 1) {
+ return null;
+ }
+ return new DocumentPath(this.tokens.subList(0, tokens.size() - 1));
+ }
+
+ /**
+ * Returns the complete list of tokens representing this path in correct
+ * order.
+ *
+ * @return a list of strings representing this path
+ */
+ public List<String> path() {
+ return ImmutableList.copyOf(tokens);
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(tokens);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (obj instanceof DocumentPath) {
+ DocumentPath that = (DocumentPath) obj;
+ return this.tokens.equals(that.tokens);
+ }
+ return false;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder stringBuilder = new StringBuilder();
+ Iterator<String> iter = tokens.iterator();
+ while (iter.hasNext()) {
+ stringBuilder.append(iter.next());
+ if (iter.hasNext()) {
+ stringBuilder.append(".");
+ }
+ }
+ return stringBuilder.toString();
+ }
+
+ @Override
+ public int compareTo(Object o) {
+ if (o instanceof DocumentPath) {
+ DocumentPath that = (DocumentPath) o;
+ int shorterLength = this.tokens.size() > that.tokens.size() ?
+ that.tokens.size() : this.tokens.size();
+ for (int i = 0; i < shorterLength; i++) {
+ if (this.tokens.get(i).compareTo(that.tokens.get(i)) != 0) {
+ return this.tokens.get(i).compareTo(that.tokens.get(i));
+ }
+ }
+
+ if (this.tokens.size() > that.tokens.size()) {
+ return 1;
+ } else if (that.tokens.size() > this.tokens.size()) {
+ return -1;
+ } else {
+ return 0;
+ }
+ }
+ throw new IllegalArgumentException("Compare can only compare objects" +
+ "of the same type.");
+ }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java b/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java
new file mode 100644
index 0000000..5156c06
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+import org.onosproject.store.primitives.DocumentTreeNode;
+
+import java.util.Iterator;
+
+/**
+ * Interface for a tree with structure wherein keys hold information
+ * about the hierarchical structure of the tree (name of parent,
+ * grandparent etc.).
+ */
+public interface DocumentTree<V> {
+
+ /**
+ * Returns the root of the tree. This will be the first part of any fully
+ * qualified path and will enable discovery of the entire tree.
+ *
+ * @return a string that is the name of the root of the tree.
+ */
+ DocumentPath root();
+
+ /**
+ * Returns a sorted list containing all key value pairs that are direct
+ * descendants of the supplied parent. The returned list will be immutable.
+ * If the specified parent does not exist this method will fail with an
+ * exception.
+ *
+ * @throws NoSuchDocumentPathException if the parent does not exist
+ * @param parentPath the path to the parent of the desired nodes
+ * @return an iterator of the children of the specified parent
+ */
+ Iterator<DocumentTreeNode<V>> getChildren(DocumentPath parentPath);
+
+ /**
+ * Returns the value associated with the supplied key or null if no such
+ * node exists.
+ *
+ * @param key the key to query
+ * @return a value or null
+ */
+ DocumentTreeNode<V> getNode(DocumentPath key);
+
+ /**
+ * Takes a string that specifies the complete path to the mapping to be
+ * added or updated and creates the key value mapping or updates the value.
+ * If the specified parent cannot be found the operation fails with an
+ * error.
+ *
+ * @throws NoSuchDocumentPathException if the specified parent does not
+ * exist.
+ * @param key the fully qualified key of the entry to be added or updated
+ * @param value the non-null value to be associated with the key
+ * @return the previous mapping or null if there was no previous mapping
+ */
+ V putNode(DocumentPath key, V value);
+
+ /**
+ * Takes the fully qualified name of the node to be added along with
+ * the value to be added. If the specified key already exists it doesnot
+ * update anything & returns false. If the parent does not exist the
+ * operation fails with an exception.
+ *
+ * @throws NoSuchDocumentPathException if the specified parent does not
+ * exist.
+ * @param key the fully qualified key of the entry to be added or updated
+ * @param value the non-null value to be associated with the key
+ * @return returns true if the mapping could be added successfully
+ */
+ boolean createNode(DocumentPath key, V value);
+
+ /**
+ * Removes the node with the specified fully qualified key. Returns null if
+ * the node did not exist. This method will throw an exception if called on
+ * a non-leaf node.
+ *
+ * @throws IllegalDocumentModificationException if the node had children.
+ * @param key the fully qualified key of the node to be removed
+ * @return the previous value of the node or null if it did not exist
+ */
+ V removeNode(DocumentPath key);
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentModificationException.java b/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentModificationException.java
new file mode 100644
index 0000000..932eeaa
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentModificationException.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+/**
+ * An exception to be thrown when a node cannot be removed normally because
+ * it does not exist or because it is not a leaf node.
+ */
+public class IllegalDocumentModificationException extends DocumentException {
+ public IllegalDocumentModificationException() {
+ }
+
+ public IllegalDocumentModificationException(String message) {
+ super(message);
+ }
+
+ public IllegalDocumentModificationException(String message,
+ Throwable cause) {
+ super(message, cause);
+ }
+
+ public IllegalDocumentModificationException(Throwable cause) {
+ super(cause);
+ }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentNameException.java b/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentNameException.java
new file mode 100644
index 0000000..487effc
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/IllegalDocumentNameException.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+/**
+ * An exception thrown when an illegally named node is submitted.
+ */
+public class IllegalDocumentNameException extends DocumentException {
+ public IllegalDocumentNameException() {
+ }
+
+ public IllegalDocumentNameException(String message) {
+ super(message);
+ }
+
+ public IllegalDocumentNameException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ public IllegalDocumentNameException(Throwable cause) {
+ super(cause);
+ }
+}
\ No newline at end of file
diff --git a/core/api/src/main/java/org/onosproject/store/service/NoSuchDocumentPathException.java b/core/api/src/main/java/org/onosproject/store/service/NoSuchDocumentPathException.java
new file mode 100644
index 0000000..048d75d
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/NoSuchDocumentPathException.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.service;
+
+/**
+ * An exception to be thrown when an invalid path is passed to the
+ * {@code DocumentTree}.
+ */
+public class NoSuchDocumentPathException extends DocumentException {
+ public NoSuchDocumentPathException() {
+ }
+
+ public NoSuchDocumentPathException(String message) {
+ super(message);
+ }
+
+ public NoSuchDocumentPathException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ public NoSuchDocumentPathException(Throwable cause) {
+ super(cause);
+ }
+}