nz.co.gregs.dbvolution.query.TreeNode Maven / Gradle / Ivy
/*
* Copyright 2014 gregory.graham.
*
* 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 nz.co.gregs.dbvolution.query;
import java.util.ArrayList;
import java.util.List;
import nz.co.gregs.dbvolution.DBRecursiveQuery;
import nz.co.gregs.dbvolution.DBRow;
import nz.co.gregs.dbvolution.datatypes.QueryableDatatype;
/**
* Encapsulates a DBRow class for use in {@link DBRecursiveQuery} tree or path.
*
*
* Use {@link #getData() } to retrieve the DBRow contain in the node, {@link #getParent()
* } to move up the hierarchy, and {@link #getChildren() } to move down it.
*
*
Support DBvolution at
* Patreon
*
* @author Gregory Graham
* @param The DBRow class
*/
public class TreeNode {
private final List> children = new ArrayList>();
private final List childrenKeys = new ArrayList();
private TreeNode parent = null;
private T data = null;
/**
* Create a new node for the DBRow
*
* @param data
*/
public TreeNode(T data) {
this.data = data;
}
/**
* Create a new node the contains the specified DBRow as the data, and the
* specified TreeNode as the parent of the node.
*
* @param data
* @param parent
*/
public TreeNode(T data, TreeNode parent) {
this.data = data;
this.parent = parent;
}
/**
* Returns a list of all known children of this node, that is all database
* rows returned by the recursive query that referenced this row.
*
* Support DBvolution at
* Patreon
*
* @return a list of TreeNodes
*/
public List> getChildren() {
return children;
}
private void setParent(TreeNode parent) {
this.parent = parent;
}
/**
* Append the supplied DBRow to the list of children for this node.
*
*
* Also adds this node as the parent of the supplied node.
*
* @param childData
*/
public void addChild(T childData) {
TreeNode child = new TreeNode(childData);
this.addChild(child);
// child.setParent(this);
// if (notAlreadyIncluded(child)) {
// this.children.add(child);
// this.childrenData.add(data.getPrimaryKeys().stringValue());
// }
}
/**
* Append the supplied DBRow to the list of children for this node.
*
*
* Also adds this node as the parent of the supplied node.
*
* @param child
*/
public void addChild(TreeNode child) {
child.setParent(this);
if (notAlreadyIncluded(child)) {
this.children.add(child);
this.childrenKeys.add(child.getKey());
}
}
private boolean notAlreadyIncluded(TreeNode child) {
return !this.children.contains(child) && !childrenKeys.contains(child.getKey());
}
/**
* Retrieves the DBRow within this node.
*
* Support DBvolution at
* Patreon
*
* @return a DBRow
*/
public T getData() {
return this.data;
}
/**
* Set the DBRow within this node.
*
* @param data
*/
public void setData(T data) {
this.data = data;
}
/**
* Indicates whether or not this node is a root node, that is it has no known
* parent.
*
* Support DBvolution at
* Patreon
*
* @return TRUE if this node is the top of a hierarchy.
*/
public boolean isRoot() {
return (this.parent == null);
}
/**
* Indicates whether or not this node is a leaf node, that is it has no known
* children.
*
* Support DBvolution at
* Patreon
*
* @return TRUE if this node is the bottom of a hierarchy.
*/
public boolean isLeaf() {
return this.children.isEmpty();
}
/**
* Remove the link to this node's parent, if any.
*
*/
public void removeParent() {
this.parent = null;
}
/**
* Retrieves the node that is the parent of this node.
*
* Support DBvolution at
* Patreon
*
* @return the TreeNode immediately above this node in the hierarchy
*/
public TreeNode getParent() {
return this.parent;
}
@Override
public String toString() {
return this.getData().toString();
}
private String getKey() {
StringBuilder returnString = new StringBuilder("");
final List> pks = this.getData().getPrimaryKeys();
for (QueryableDatatype pk : pks) {
returnString.append("&&").append(pk.stringValue());
}
return returnString.toString();
}
}