/*
 * The MIT License
 *
 * Copyright (c) 2013, Magnus Sandberg
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package jenkins.advancedqueue.priority.strategy;

import hudson.Extension;
import hudson.model.ParametersAction;
import hudson.model.Queue;
import hudson.model.StringParameterValue;

import java.util.List;

import org.kohsuke.stapler.DataBoundConstructor;

/**
 * @author Magnus Sandberg
 * @since 2.0
 */
public class BuildParameterStrategy extends AbstractDynamicPriorityStrategy {

	@Extension
	static public class BuildParameterStrategyDescriptor extends
			AbstractDynamicPriorityStrategyDescriptor {

		public BuildParameterStrategyDescriptor() {
			super("Use Priority from Build Parameter");
		}
	};

	private final String parameterName;

	@DataBoundConstructor
	public BuildParameterStrategy(String parameterName) {
		this.parameterName = parameterName;
	}

	public String getParameterName() {
		return parameterName;
	}

	private Integer getPriorityInternal(Queue.Item item) {
		List<ParametersAction> actions = item
				.getActions(ParametersAction.class);
		for (ParametersAction action : actions) {
			StringParameterValue parameterValue = (StringParameterValue) action
					.getParameter("parameterName");
			if (parameterValue != null) {
				String value = parameterValue.value;
				try {
					return Integer.parseInt(value);
				} catch (NumberFormatException e) {
					// continue
				}
			}
		}
		return null;
	}

	public int getPriority(Queue.Item item) {
		return getPriorityInternal(item);
	}

	@Override
	public boolean isApplicable(Queue.Item item) {
		return getPriorityInternal(item) != null;
	}
}

/*
 * The MIT License
 *
 * Copyright (c) 2013, Magnus Sandberg
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package jenkins.advancedqueue.priority.strategy;

import hudson.Extension;
import hudson.model.ParametersAction;
import hudson.model.Queue;
import hudson.model.StringParameterValue;

import java.util.List;

import org.kohsuke.stapler.DataBoundConstructor;

/**
 * @author Magnus Sandberg
 * @since 2.0
 */
public class BuildParameterStrategy extends AbstractDynamicPriorityStrategy {

	@Extension
	static public class BuildParameterStrategyDescriptor extends
			AbstractDynamicPriorityStrategyDescriptor {

		public BuildParameterStrategyDescriptor() {
			super("Use Priority from Build Parameter");
		}
	};

	private final String parameterName;

	@DataBoundConstructor
	public BuildParameterStrategy(String parameterName) {
		this.parameterName = parameterName;
	}

	public String getParameterName() {
		return parameterName;
	}

	private Integer getPriorityInternal(Queue.Item item) {
		List<ParametersAction> actions = item
				.getActions(ParametersAction.class);
		for (ParametersAction action : actions) {
			StringParameterValue parameterValue = (StringParameterValue) action
					.getParameter(parameterName);
			if (parameterValue != null) {
				String value = parameterValue.value;
				try {
					return Integer.parseInt(value);
				} catch (NumberFormatException e) {
					// continue
				}
			}
		}
		return null;
	}

	public int getPriority(Queue.Item item) {
		return getPriorityInternal(item);
	}

	@Override
	public boolean isApplicable(Queue.Item item) {
		return getPriorityInternal(item) != null;
	}
}

Use parameterName (variable) not "parameterName" (literal)