ca.hedlund.jiss.preprocessor.InfoPreprocessor.java Source code

Introduction

Here is the source code for ca.hedlund.jiss.preprocessor.InfoPreprocessor.java

Source

/*
 * jiss-core
 * Copyright (C) 2015, Gregory Hedlund <ghedlund@mun.ca>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package ca.hedlund.jiss.preprocessor;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineFactory;

import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;

import ca.hedlund.jiss.JissModel;
import ca.hedlund.jiss.JissPreprocessor;

/**
 * Handles the command 'jiss::info'
 * Which prints basic information about jiss.
 *
 */
public class InfoPreprocessor implements JissPreprocessor {

    private final static String INFO_TXT = "Java Interactive Scripting Shell (jiss) 0.1";

    private final static String INFO_CMD = "jiss::info";

    @Override
    public boolean preprocessCommand(JissModel jissModel, String orig, StringBuffer cmd) {
        final String c = cmd.toString();
        if (c.equals(INFO_CMD)) {
            // clear string
            cmd.setLength(0);

            final ScriptEngine se = jissModel.getScriptEngine();
            final ScriptEngineFactory seFactory = se.getFactory();

            final boolean incnl = !seFactory.getOutputStatement("").startsWith("println");

            final String infoCmd = seFactory.getOutputStatement(INFO_TXT + (incnl ? "\\n" : ""));
            final String langCmd = seFactory.getOutputStatement("Language:" + seFactory.getLanguageName() + " "
                    + seFactory.getLanguageVersion() + (incnl ? "\\n" : ""));
            final String engineCmd = seFactory.getOutputStatement("Engine:" + seFactory.getEngineName() + " "
                    + seFactory.getEngineVersion() + (incnl ? "\\n" : ""));
            final String program = seFactory.getProgram(infoCmd, langCmd, engineCmd);
            cmd.append(StringEscapeUtils.unescapeJava(program));
        }
        // we want the scripting engine to handle the replaced command
        return false;
    }

}