/*
 * #%L
 * ImageJ software for multidimensional image processing and analysis.
 * %%
 * Copyright (C) 2014 - 2016 Board of Regents of the University of
 * Wisconsin-Madison, University of Konstanz and Brian Northan.
 * %%
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * #L%
 */

package net.imagej.ops;

import org.scijava.Priority;
import org.scijava.command.Command;
import org.scijava.command.CommandService;
import org.scijava.module.Module;
import org.scijava.module.process.AbstractPreprocessorPlugin;
import org.scijava.module.process.PreprocessorPlugin;
import org.scijava.plugin.Parameter;
import org.scijava.plugin.Plugin;

/**
 * A preprocessor plugin that injects an {@link OpEnvironment} into {@link Op}
 * instances. This is needed when the {@link Op} is executed as a
 * {@link Command} via {@link CommandService#run}.
 * 
 * @author Curtis Rueden
 */
@Plugin(type = PreprocessorPlugin.class, priority = Priority.VERY_HIGH_PRIORITY)
public class OpEnvironmentPreprocessor extends AbstractPreprocessorPlugin {

	@Parameter(required = false)
	private OpService ops;

	// -- ModuleProcessor methods --

	@Override
	public void process(final Module module) {
		if (ops == null) return; // no op service available to inject

		final Object delegate = module.getDelegateObject();
		if (!(delegate instanceof Op)) return; // command is not an op

		final Op op = (Op) delegate;
		if (op.ops() != null) return; // op already has an environment

		op.setEnvironment(ops);
	}

}

Add preprocessor which injects the OpEnvironment
Add preprocessor which injects the OpEnvironment

When running an op directly as a command via the CommandService,
the created Op instance will lack its usual OpEnvironment.

This preprocessor remedies that problem by injecting the
OpService as the default OpEnvironment in that scenario.

This commit is dedicated to Kyle Harrington!
