FileHelper.java

package advancedsystemsmanager.helpers;

import advancedsystemsmanager.AdvancedSystemsManager;
import org.apache.commons.io.FileUtils;

import java.io.*;
import java.net.URL;

/**
 * Various functions to help with files
 */
public class FileHelper
{
    /**
     * Read a file from jar
     *
     * @param classFromJar A class from the jar in question
     * @param file         File to read
     * @return the InputStream
     */
    public static InputStream getInputStreamFromJar(Class<?> classFromJar, String file)
    {
        URL url = classFromJar.getResource(file);
        try
        {
            return url.openStream();
        } catch (IOException e)
        {
            AdvancedSystemsManager.log.warn("Couldn't read file from jar!");
            AdvancedSystemsManager.log.info("This is a bug, please report it to the mod author!");
            throw new RuntimeException(e);
        }
    }

    /**
     * Get a JSON file from the default data location
     *
     * @param classFromJar the class that makes the call
     * @param file         String[2] array, 0 is source, 1 is destination
     * @param alwaysCopy   set ot true to always make a fresh copy
     * @return the requested JSON file in an InputStream. Throws IOException if something goes wrong
     */
    public static InputStream getJsonFile(Class<?> classFromJar, String[] file, boolean alwaysCopy)
    {
        File dataFile = new File(file[1]);

        if (!dataFile.isFile() || alwaysCopy)
        {
            FileHelper.copyFromJar(classFromJar, file[0], file[1]);

            // If the file was copied, get the file again
            dataFile = new File(file[1]);
        }

        if (dataFile.isFile())
        {
            InputStream stream;
            try
            {
                stream = new FileInputStream(dataFile);
            } catch (FileNotFoundException e)
            {
                throw new RuntimeException(e);
            }
            return stream;
        }
        throw new RuntimeException(); // this should never be reached
    }

    /**
     * @param classFromJar    A class from the jar in question
     * @param fileSource      File to copy
     * @param fileDestination File to copy to
     */
    public static void copyFromJar(Class<?> classFromJar, String fileSource, String fileDestination)
    {
        URL source = classFromJar.getResource(fileSource);
        File destination = new File(fileDestination);

        try
        {
            FileUtils.copyURLToFile(source, destination);
        } catch (IOException e)
        {
            AdvancedSystemsManager.log.warn("Couldn't load file from jar!");
            AdvancedSystemsManager.log.info("This is a bug, please report it to the mod author!");

            if (AdvancedSystemsManager.DEV_ENVIRONMENT)
            {
                throw new RuntimeException(e);
            }
        }
    }

    /**
     * Check if file exits in the jar
     *
     * @param classFromJar
     * @param fileSource
     * @return
     */
    public static boolean doesFileExistInJar(Class<?> classFromJar, String fileSource)
    {
        try
        {
            URL source = classFromJar.getResource(fileSource);
            return source != null;
        } catch (NullPointerException e)
        {
            return false;
        }
    }

    /**
     * Check if file exits in the config folder
     *
     * @param file
     * @return
     */
    public static boolean doesFileExist(String file)
    {
        try
        {
            new FileInputStream(FileUtils.getFile(file));
            return true;
        } catch (FileNotFoundException e)
        {
            return false;
        }
    }

    /**
     * Get a file from the config folder
     *
     * @param file the fileName
     * @return
     */
    public static FileInputStream getFile(String file)
    {
        try
        {
            return new FileInputStream(FileUtils.getFile(file));
        } catch (FileNotFoundException e)
        {
            throw new RuntimeException(e);
        }
    }
}