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package org.apache.juneau.rest.arg;

import org.apache.juneau.reflect.*;
import org.apache.juneau.rest.*;
import org.apache.juneau.rest.annotation.*;

/**
 * Resolves method parameters annotated with {@link Method} on {@link RestOp}-annotated Java methods.
 *
 * <p>
 * The parameter value is resolved using:
 * <p class='bjava'>
 * 	<jv>opSession</jv>
 * 		.{@link RestOpSession#getRequest() getRequest}()
 * 		.{@link RestRequest#getMethod() getMethod}();
 * </p>
 *
 * <p>
 * The parameter type must be {@link String}.
 *
 * <ul class='seealso'>
 * 	<li class='link'>{@doc jrs.JavaMethodParameters}
 * 	<li class='extlink'>{@source}
 * </ul>
 */
public class MethodArg implements RestOpArg {

	/**
	 * Static creator.
	 *
	 * @param paramInfo The Java method parameter being resolved.
	 * @return A new {@link MethodArg}, or <jk>null</jk> if the parameter isn't annotated with {@link Method}.
	 */
	public static MethodArg create(ParamInfo paramInfo) {
		if (paramInfo.hasAnnotation(Method.class))
			return new MethodArg();
		return null;
	}

	/**
	 * Constructor.
	 */
	protected MethodArg() {
	}

	@Override /* RestOpArg */
	public Object resolve(RestOpSession opSession) throws Exception {
		return opSession.getRequest().getMethod();
	}
}
