org.universAAL.support.directives.checks.MainMethodCheck.java Source code

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Here is the source code for org.universAAL.support.directives.checks.MainMethodCheck.java

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/*******************************************************************************
 * Copyright 2013 Universidad Politcnica de Madrid
 *
 * 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.universAAL.support.directives.checks;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.io.FileUtils;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.plugin.logging.Log;
import org.apache.maven.project.MavenProject;
import org.universAAL.support.directives.api.APICheck;
import org.universAAL.support.directives.util.SourceChecker;
import org.universAAL.support.directives.util.SourceExplorer;

/**
 * @author amedrano
 *
 */
public class MainMethodCheck implements SourceChecker, APICheck {

    public static String MAIN_REGEXP = "(public\\s+)?static\\s+(public\\s+)?void\\s+main\\s*\\(\\s*String(\\s*\\[\\])?\\s+\\w+(\\s*\\[\\])?\\s*\\)";

    private static Pattern MAIN_PATTERN = Pattern.compile(MAIN_REGEXP);

    /** {@ inheritDoc}    */
    public boolean check(MavenProject mavenproject, Log log) throws MojoExecutionException, MojoFailureException {
        SourceExplorer se = new SourceExplorer(this);
        ArrayList<File> conflicted = se.walk(mavenproject.getBasedir() + "/src/main/java/");
        if (conflicted.size() > 0) {
            String m = "The following Files contain a main method:\n";
            for (java.util.Iterator<File> iterator = conflicted.iterator(); iterator.hasNext();) {
                m += "\t" + iterator.next().getAbsolutePath() + "\n";
            }
            m += "There should not be any main method in a Library. Consider moving this code to a Junit Test.";
            throw new MojoFailureException(m);
        }
        return true;
    }

    /** {@ inheritDoc}    */
    public boolean passesTest(File sourceFile) {
        try {
            String code = FileUtils.readFileToString(sourceFile);
            code = new CommentRemoverStateMachine().removeComments(code);
            Matcher m = MAIN_PATTERN.matcher(code);
            return !m.find();
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }

    public static class CommentRemoverStateMachine {

        int state = 0;

        int nextState(char c) {
            switch (state) {
            case 0:
                if (c == '/')
                    return 1;
                else
                    return 0;
            case 1:
                if (c == '/')
                    return 2;
                else if (c == '*')
                    return 3;
                else
                    return 0;
            case 2:
                if (c == '\n')
                    return 0;
                else
                    return 2;
            case 3:
                if (c == '*')
                    return 4;
                else
                    return 3;
            case 4:
                if (c == '/')
                    return 5;
                else if (c == '*')
                    return 4;
                else
                    return 3;
            case 5:
                return 0;
            default:
                break;
            }
            return 0;
        }

        String removeComments(String s) {
            StringBuffer sb = new StringBuffer();
            for (int i = 0; i < s.length(); i++) {
                state = nextState(s.charAt(i));
                if (state == 0) {
                    sb.append(s.charAt(i));
                }
            }
            return sb.toString();
        }

    }

}