DefaultOption.java

/*
 * Copyright 2013-2017 the original author or authors.
 *
 * 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.springframework.cassandra.core.keyspace;

import static org.springframework.cassandra.core.cql.CqlStringUtils.*;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.Collection;
import java.util.Map;

import org.springframework.util.Assert;

/**
 * A default implementation of {@link Option}.
 *
 * @author Matthew T. Adams
 * @author Mark Paluch
 */
public class DefaultOption implements Option {

	private String name;

	private Class<?> type;

	private boolean requiresValue;

	private boolean escapesValue;

	private boolean quotesValue;

	public DefaultOption(String name, Class<?> type, boolean requiresValue, boolean escapesValue, boolean quotesValue) {

		setName(name);
		setType(type);

		this.requiresValue = requiresValue;
		this.escapesValue = escapesValue;
		this.quotesValue = quotesValue;

	}

	protected void setName(String name) {

		Assert.hasText(name, "Name must not be null or empty");
		this.name = name;
	}

	protected void setType(Class<?> type) {
		if (type != null) {
			if (type.isInterface() && !(Map.class.isAssignableFrom(type) || Collection.class.isAssignableFrom(type))) {
				throw new IllegalArgumentException("given type [" + type.getName() + "] must be a class, Map or Collection");
			}
		}
		this.type = type;
	}

	@SuppressWarnings({ "unchecked", "rawtypes" })
	public boolean isCoerceable(Object value) {
		if (value == null || type == null) {
			return true;
		}

		// check map
		if (Map.class.isAssignableFrom(type)) {
			return Map.class.isAssignableFrom(value.getClass());
		}
		// check collection
		if (Collection.class.isAssignableFrom(type)) {
			return Collection.class.isAssignableFrom(value.getClass());
		}
		// check enum
		if (type.isEnum()) {
			try {
				String name = value instanceof Enum ? name = ((Enum) value).name() : value.toString();
				Enum.valueOf((Class<? extends Enum>) type, name);
				return true;
			} catch (NullPointerException x) {
				return false;
			} catch (IllegalArgumentException x) {
				return false;
			}
		}

		// check class via String constructor
		try {
			Constructor<?> ctor = type.getConstructor(String.class);
			if (!ctor.isAccessible()) {
				ctor.setAccessible(true);
			}
			ctor.newInstance(value.toString());
			return true;
		} catch (InstantiationException e) {} catch (IllegalAccessException e) {} catch (IllegalArgumentException e) {} catch (InvocationTargetException e) {} catch (NoSuchMethodException e) {} catch (SecurityException e) {}
		return false;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#getType()
	 */
	public Class<?> getType() {
		return type;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#getName()
	 */
	public String getName() {
		return name;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#takesValue()
	 */
	public boolean takesValue() {
		return type != null;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#requiresValue()
	 */
	public boolean requiresValue() {
		return this.requiresValue;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#escapesValue()
	 */
	public boolean escapesValue() {
		return this.escapesValue;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#quotesValue()
	 */
	public boolean quotesValue() {
		return this.quotesValue;
	}

	/* (non-Javadoc)
	 * @see org.springframework.cassandra.core.keyspace.Option#checkValue(java.lang.Object)
	 */
	public void checkValue(Object value) {
		if (takesValue()) {
			if (value == null) {
				if (requiresValue) {
					throw new IllegalArgumentException("Option [" + getName() + "] requires a value");
				}
				return; // doesn't require a value, so null is ok
			}
			// else value is not null
			if (isCoerceable(value)) {
				return;
			}
			// else value is not coerceable into the expected type
			throw new IllegalArgumentException(
					"Option [" + getName() + "] takes value coerceable to type [" + getType().getName() + "]");
		}
		// else this option doesn't take a value
		if (value != null) {
			throw new IllegalArgumentException("Option [" + getName() + "] takes no value");
		}
	}

	public String toString(Object value) {
		if (value == null) {
			return null;
		}
		checkValue(value);

		String string = value.toString();
		string = escapesValue ? escapeSingle(string) : string;
		string = quotesValue ? singleQuote(string) : string;
		return string;
	}

	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		return "[name=" + name + ", type=" + type.getName() + ", requiresValue=" + requiresValue + ", escapesValue="
				+ escapesValue + ", quotesValue=" + quotesValue + "]";
	}
}