Java tutorial
/* * Copyright 2014 Yaroslav Mytkalyk * 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.docd.purefm.commandline; import com.docd.purefm.file.GenericFile; import org.apache.commons.io.FileUtils; import android.support.annotation.NonNull; import java.util.List; /** * du - estimate file space usage * -s display only a total for each argument */ public final class CommandDu extends BusyboxCommand { public CommandDu(@NonNull final GenericFile file) { super("du -s " + file.getAbsolutePath()); } public static long du_s(@NonNull final GenericFile file) { final List<String> result = CommandLine.executeForResult(new CommandDu(file)); if (result == null || result.isEmpty()) { return 0L; } final String res = result.get(0); final int resLength = res.length(); final StringBuilder lengthString = new StringBuilder(resLength); for (int i = 0; i < resLength; i++) { final char character = res.charAt(i); if (Character.isDigit(character)) { lengthString.append(character); } else { break; } } try { return Long.parseLong(lengthString.toString()) * FileUtils.ONE_KB; } catch (NumberFormatException e) { return 0L; } } }