com.jkoolcloud.tnt4j.streams.utils.StreamsScriptingUtils.java Source code

Introduction

Here is the source code for com.jkoolcloud.tnt4j.streams.utils.StreamsScriptingUtils.java

Source

/*
 * Copyright 2014-2017 JKOOL, LLC.
 *
 * 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 com.jkoolcloud.tnt4j.streams.utils;

import java.util.*;

import org.apache.commons.lang3.StringUtils;
import org.codehaus.groovy.control.CompilerConfiguration;
import org.codehaus.groovy.control.customizers.CompilationCustomizer;
import org.codehaus.groovy.control.customizers.ImportCustomizer;

/**
 * General scripting utility methods used by TNT4J-Streams.
 * 
 * @version $Revision: 1 $
 */
public final class StreamsScriptingUtils {
    private static CompilerConfiguration DEFAULT_GROOVY_CONFIGURATION;
    private static String DEFAULT_JS_CODE_IMPORTS;

    private static final Set<String> DEFAULT_IMPORT_PACKAGES = new HashSet<>();

    static {
        initDefaultImportPackages();
    }

    private StreamsScriptingUtils() {
    }

    /**
     * Initiates default set of Java API imported packages.
     */
    private static void initDefaultImportPackages() {
        try {
            Properties p = Utils.loadPropertiesResources("scripting.properties"); // NON-NLS

            for (String pName : p.stringPropertyNames()) {
                if (pName.endsWith(".scripting.import.packages")) { // NON-NLS
                    String importPackages = p.getProperty(pName);

                    if (StringUtils.isNotEmpty(importPackages)) {
                        String[] pArray = importPackages.split(";");

                        Collections.addAll(DEFAULT_IMPORT_PACKAGES, pArray);
                    }
                }
            }
        } catch (Exception exc) {
        }
    }

    /**
     * Returns Groovy compiler configuration containing default set of Java API imported packages.
     * 
     * @return Groovy compiler compiler configuration containing default set of Java API imported packages
     */
    public static CompilerConfiguration getDefaultGroovyCompilerConfig() {
        if (DEFAULT_GROOVY_CONFIGURATION == null) {
            DEFAULT_GROOVY_CONFIGURATION = initDefaultGroovyCompilerConfig();
        }

        return DEFAULT_GROOVY_CONFIGURATION;
    }

    private static CompilerConfiguration initDefaultGroovyCompilerConfig() {
        CompilerConfiguration cc = new CompilerConfiguration();

        // inject default imports
        ImportCustomizer ic = new ImportCustomizer();

        for (String pckg : DEFAULT_IMPORT_PACKAGES) {
            ic.addStarImports(pckg);
        }

        cc.addCompilationCustomizers(ic);

        return cc;
    }

    /**
     * Wraps JS script code with default set of Java API imported packages.
     *
     * @param script
     *            script code to wrap with default imports
     * @return default imports wrapped JS script code
     */
    public static String addDefaultJSScriptImports(String script) {
        if (DEFAULT_JS_CODE_IMPORTS == null) {
            DEFAULT_JS_CODE_IMPORTS = initDefaultJSScriptImports();
        }

        return DEFAULT_JS_CODE_IMPORTS + script;
    }

    private static String initDefaultJSScriptImports() {
        StringBuilder sb = new StringBuilder();

        for (String pckg : DEFAULT_IMPORT_PACKAGES) {
            sb.append("importPackage(").append(pckg).append(");\n"); // NON-NLS
        }

        return sb.toString();
    }

    /**
     * Adds package name to default set of Java API imported packages.
     * 
     * @param pckg
     *            package name to add
     */
    public static void registerDefaultImportPackage(String pckg) {
        DEFAULT_IMPORT_PACKAGES.add(pckg);

        if (DEFAULT_GROOVY_CONFIGURATION != null) {
            List<CompilationCustomizer> ccList = DEFAULT_GROOVY_CONFIGURATION.getCompilationCustomizers();

            for (CompilationCustomizer cc : ccList) {
                if (cc instanceof ImportCustomizer) {
                    ((ImportCustomizer) cc).addStarImports(pckg);
                }
            }
        }

        if (DEFAULT_JS_CODE_IMPORTS != null) {
            StringBuilder sb = new StringBuilder(DEFAULT_JS_CODE_IMPORTS);

            sb.append("importPackage(").append(pckg).append(");\n"); // NON-NLS

            DEFAULT_JS_CODE_IMPORTS = sb.toString();
        }
    }
}