ICUAndroidBridge.java :  » UnTagged » android-zmanim » com » ibm » icu » Android Open Source

package com.ibm.icu;

import android.content.res.AssetManager;

import java.io.FilenameFilter;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.MissingResourceException;

/**
 * Bridge that will handle things that ICU would normally want to do one way, but must do differently
 *  in order to play nicely with Android.
 */
public class ICUAndroidBridge {

  /**
   * Only one instance of this guy.
   */
  private static ICUAndroidBridge                           instance;

  /**
   * ICU would normally want to use the Class.getResource() and Class.getResourceAsStream() to read things.
   *  The Android way, however, says that you go through the asset manager.
   */
  private final AssetManager                                assetManager;

//  public final List<String>                                 whatDidWeTryToLoad = new ArrayList<String>();

  public static void create(
    AssetManager  assetManager
  ) {

    if ( null == instance ) {
      instance = new ICUAndroidBridge( assetManager );
    }
  }


  public static ICUAndroidBridge get() {
    return instance;
  }


  private ICUAndroidBridge( AssetManager assetManager ) {
    this.assetManager = assetManager;
  }


  public boolean resourceExists(
    String resourceName
  ) {

    int lastSlash = resourceName.lastIndexOf( "/" );

    String directory;
    String file;
    if ( -1 != lastSlash ) {
      directory = resourceName.substring( 0, lastSlash - 1 );
      file = resourceName.substring( lastSlash );
    }
    else {
      directory = "";
      file = resourceName;
    }

    // Make sure we're not starting with a "/"... that won't work here...
    if ( directory.startsWith( "/" ) ) {
      directory = directory.substring( 1 );
    }


    try {
      String [] files = assetManager.list( directory );
      for ( String f : files ) {
        if ( file.equals( f  ) ) {
          return true;
        }
      }
    }
    catch ( IOException e ) {
      // Ignore.
    }

    return false;
  }


  public ArrayList<String> list(
    String          directory,
    FilenameFilter  filenameFilter
  ) {

    // Asset manager doesn't like to do a listing if the the directory ends with a '/'...
    if ( directory.endsWith( "/" ) ) {
      directory = directory.substring( 0, directory.length() - 1 );
    }

    ArrayList<String> listing = new ArrayList<String>();

    try {
      String [] files = assetManager.list( directory );
      for ( String f : files ) {
        if ( filenameFilter.accept( null, f ) ) {
          listing.add( f );
        }
      }
    }
    catch ( IOException e ) {
      return null;
    }

    return listing;
  }


  public InputStream open(
    String  resourceName,
    boolean failIfNotPresent
  ) {

    InputStream i;

    // Make sure we're not starting with a "/"... that won't work here...
    if ( resourceName.startsWith( "/" ) ) {
      resourceName = resourceName.substring( 1 );
    }

    try {
//      whatDidWeTryToLoad.add( resourceName );
      i = assetManager.open( resourceName );
    }
    catch ( IOException e ) {
      if ( failIfNotPresent ) {
        throw new MissingResourceException("could not locate data " + resourceName, "", resourceName);
      }

      i = null;
    }

    return i;
  }


} // End of ICUAndroidBridge interface