com.dooapp.gaedo.finders.collections.Matcher Maven / Gradle / Ivy

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Contains the collections implementation, and only depend upon gaedo-definition
There is a newer version: 1.0.16
/**
 * 
 */
package com.dooapp.gaedo.finders.collections;

import java.util.Stack;

import com.dooapp.gaedo.finders.expressions.AndQueryExpression;
import com.dooapp.gaedo.finders.expressions.AnythingExpression;
import com.dooapp.gaedo.finders.expressions.CollectionContaingExpression;
import com.dooapp.gaedo.finders.expressions.ContainsStringExpression;
import com.dooapp.gaedo.finders.expressions.EndsWithExpression;
import com.dooapp.gaedo.finders.expressions.EqualsExpression;
import com.dooapp.gaedo.finders.expressions.GreaterThanExpression;
import com.dooapp.gaedo.finders.expressions.LowerThanExpression;
import com.dooapp.gaedo.finders.expressions.MapContainingKeyExpression;
import com.dooapp.gaedo.finders.expressions.NotQueryExpression;
import com.dooapp.gaedo.finders.expressions.OrQueryExpression;
import com.dooapp.gaedo.finders.expressions.QueryExpressionVisitor;
import com.dooapp.gaedo.finders.expressions.StartsWithExpression;
import com.dooapp.gaedo.finders.informers.MapContainingValueExpression;

/**
 * Matcher will be used to check if input object matches local constraints
 * @author ndx
 *
 * @param 
 */
public class Matcher implements QueryExpressionVisitor {
	/**
	 * A stack is maintained during visiting elements, but ony its 0 element is interesting
	 */
	private Stack> evaluators = new Stack>();
	
	public Matcher() {
		evaluators.push(new AndEvaluator());
	}

	public void endVisit(AndQueryExpression andQueryExpression) {
		evaluators.pop();
	}

	public void endVisit(NotQueryExpression notQueryExpression) {
		evaluators.pop();
	}

	public void endVisit(OrQueryExpression orQueryExpression) {
		evaluators.pop();
	}

	/**
	 * Check if this matcher matches the given object. For that, all inner matchers are used. The root matcher will be used to start evaluating. 
	 * Hopefully, this root matcher is a And one
	 * @param element
	 */
	public boolean matches(DataType element) {
		return evaluators.get(0).matches(element);
	}

	public void startVisit(AndQueryExpression andQueryExpression) {
		add(new AndEvaluator());
	}

	/**
	 * Adds an evaluator on the top of the stack
	 * @param evaluator
	 */
	private void add(Evaluator evaluator) {
		evaluators.peek().add(evaluator);
		evaluators.push(evaluator);
	}

	public void startVisit(NotQueryExpression notQueryExpression) {
		add(new NotEvaluator());
	}

	public void startVisit(OrQueryExpression orQueryExpression) {
		add(new OrEvaluator());
	}

	@Override
	public void visit(AnythingExpression expression) {
		evaluators.peek().add(new AnythingEvaluator(expression.getField()));
	}
	
	public void visit(EqualsExpression expression) {
		evaluators.peek().add(new EqualsEvaluator(expression.getField(), expression.getValue()));
	}

	@Override
	public String toString() {
		return evaluators.get(0).toString();
	}

	public > void visit(GreaterThanExpression expression) {
		evaluators.peek().add(new GreaterThanEvaluator(expression.getField(), expression.isStrictly(), expression.getValue()));
		
	}

	public > void visit(LowerThanExpression expression) {
		evaluators.peek().add(new LowerThanEvaluator(expression.getField(), expression.isStrictly(), expression.getValue()));
	}

	@Override
	public void visit(ContainsStringExpression expression) {
		evaluators.peek().add(new ContainsStringEvaluator(expression.getField(), expression.getContained()));
	}

	@Override
	public void visit(StartsWithExpression expression) {
		evaluators.peek().add(new StartsWithEvaluator(expression.getField(), expression.getStart()));
	}

	@Override
	public void visit(EndsWithExpression expression) {
		evaluators.peek().add(new EndsWithEvaluator(expression.getField(), expression.getEnd()));
	}

	@Override
	public void visit(CollectionContaingExpression expression) {
		evaluators.peek().add(new CollectionContainingEvaluator(expression.getField(), expression.getContained()));
		
	}

	@Override
	public void visit(MapContainingValueExpression expression) {
		evaluators.peek().add(new MapContainingKeyEvaluator(expression.getField(), expression.getContained()));
	}

	@Override
	public void visit(MapContainingKeyExpression expression) {
		evaluators.peek().add(new MapContainingValueEvaluator(expression.getField(), expression.getContained()));
	}
}