com.rabbitmq.jms.parse.sql.SqlParseTree Maven / Gradle / Ivy
/* Copyright (c) 2013 Pivotal Software, Inc. All rights reserved. */
package com.rabbitmq.jms.parse.sql;
import java.util.ArrayList;
import com.rabbitmq.jms.parse.ParseTree;
/**
* Tree used to hold a parsed SQL (selector) expression. The nodes are of type {@link SqlTreeNode}.
*
*/
class SqlParseTree implements ParseTree {
private final SqlTreeNode node;
private final SqlParseTree[] children;
private final SqlTreeNode[] nodes;
/**
* Tree constructor: takes the node value and the children; both are final fields of the tree.
* @param node - the node value of the (root of the) tree.
* @param children - a series of trees; omitting these arguments will imply a zero-length array of trees.
*/
public SqlParseTree(SqlTreeNode node, SqlParseTree... children) {
this.node = node;
this.children = children;
this.nodes = genNodes(children);
}
@Override
public SqlTreeNode getNode() {
return this.node;
}
@Override
public int getNumberOfChildren() {
return this.children.length;
}
@Override
public SqlParseTree[] getChildren() {
return this.children;
}
/**
* @return an array of {@link String}s which form a readable representation of the tree.
*/
String[] formattedTree() {
ArrayList lines = new ArrayList();
SqlToken tokVal = this.node.value();
lines.add(this.node.treeType().toString() + (tokVal == null ? ":" : ": " + tokVal));
for (SqlParseTree child: this.children) {
String[] childLines = child.formattedTree();
for (String childLine: childLines) {
lines.add(" " + childLine);
}
}
return lines.toArray(new String[lines.size()]);
}
@Override
public SqlTreeNode[] getChildNodes() {
return this.nodes;
}
private static final SqlTreeNode[] genNodes(SqlParseTree[] children) {
SqlTreeNode[] nodes = new SqlTreeNode[children.length];
for (int i=0; i