com.epam.dlab.Help.java Source code

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Here is the source code for com.epam.dlab.Help.java

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/***************************************************************************
    
Copyright (c) 2016, EPAM SYSTEMS INC
    
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.epam.dlab;

import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;

import com.epam.dlab.core.BillingUtils;
import com.epam.dlab.core.ModuleType;
import com.epam.dlab.exceptions.InitializationException;
import com.fasterxml.jackson.annotation.JsonClassDescription;
import com.fasterxml.jackson.annotation.JsonTypeName;

/** Print help for billing tool.
 */
public class Help {

    private Help() {
    }

    /** Print help to console.
     * @param resourceName the name of resource.
     * @param substitute - map for substitution in help content.
     * @throws InitializationException
     */
    private static void printHelp(String resourceName, Map<String, String> substitute)
            throws InitializationException {
        List<String> list = BillingUtils
                .getResourceAsList("/" + Help.class.getName() + "." + resourceName + ".txt");
        String help = StringUtils.join(list, System.lineSeparator());

        if (substitute == null) {
            substitute = new HashMap<>();
        }
        substitute.put("classname", BillingScheduler.class.getName());

        for (String key : substitute.keySet()) {
            help = StringUtils.replace(help, "${" + key.toUpperCase() + "}", substitute.get(key));
        }
        System.out.println(help);
    }

    /** Create and return substitutions for names of modules.
     * @return
     * @throws InitializationException
     */
    private static Map<String, String> findModules() throws InitializationException {
        List<Class<?>> modules = BillingUtils.getModuleClassList();
        Map<String, String> substitute = new HashMap<>();

        for (Class<?> module : modules) {
            ModuleType type = BillingUtils.getModuleType(module);
            JsonTypeName typeName = module.getAnnotation(JsonTypeName.class);
            if (typeName != null) {
                String typeNames = substitute.get(type.toString() + "s");
                typeNames = (typeNames == null ? typeName.value() : typeNames + ", " + typeName.value());
                substitute.put(type.toString() + "s", typeNames);
            }
        }

        return substitute;
    }

    /** Find and return help for module.
     * @param type the type of module.
     * @param name the name of module.
     * @throws InitializationException
     */
    private static String findModuleHelp(ModuleType type, String name) throws InitializationException {
        List<Class<?>> modules = BillingUtils.getModuleClassList();
        String typeNames = null;
        for (Class<?> module : modules) {
            ModuleType t = BillingUtils.getModuleType(module);
            if (t == type) {
                JsonTypeName typeName = module.getAnnotation(JsonTypeName.class);
                if (typeName != null) {
                    if (name.equals(typeName.value())) {
                        JsonClassDescription description = module.getAnnotation(JsonClassDescription.class);
                        if (description != null) {
                            return description.value();
                        }
                        throw new InitializationException("Help for " + type + " " + name + " not found");
                    } else {
                        typeNames = (typeNames == null ? typeName.value() : typeNames + ", " + typeName.value());
                    }
                }
            }
        }
        throw new InitializationException("Module for " + type + " " + name + " not found."
                + (typeNames == null ? "" : " Module type must be one of next: " + typeNames));
    }

    /** Print help screen for billing tool. 
     * @throws InitializationException */
    public static void usage(String... args) throws InitializationException {
        if (args == null || args.length == 0) {
            printHelp("usage", null);
        } else if (args[0].equalsIgnoreCase("conf")) {
            printHelp("conf", findModules());
        } else {
            ModuleType type = ModuleType.of(args[0]);
            if (type == null) {
                System.out.println("Unknown --help " + args[0] + " command.");
            } else if (args.length < 2) {
                System.out.println("Missing the type of module.");
                String typeNames = findModules().get(type.toString() + "s");
                if (typeNames != null) {
                    System.out.println("Must be one of next: " + typeNames);
                }
            } else if (args.length > 2) {
                System.out.println("Extra arguments in command: "
                        + StringUtils.join(Arrays.copyOfRange(args, 2, args.length), " "));
            } else {
                System.out.println(findModuleHelp(type, args[1]));
            }
        }
    }
}