FileOperator

使用(Usage)

1. Project build.gradle:

repositories {
 maven { url 'https://dl.bintray.com/javakam/FileOperator' }
}

2. 依赖(dependencies)

implementation 'ando.file:core:1.3.1' //核心库必选
implementation 'ando.file:android-q:1.3.1' //AndroidQ & Android 11 兼容库
implementation 'ando.file:compressor:1.3.1' //图片压缩,核心算法采用 Luban
implementation 'ando.file:selector:1.3.1' //文件选择器

3. Application中初始化(Initialization in Application)

FileOperator.init(this,BuildConfig.DEBUG)

4. 混淆(Proguard)

预览(Preview)

文件选择

Usage:

1. 单选图片(Single selection picture)

val optionsImage = FileSelectOptions().apply {
 fileType = FileType.IMAGE
 fileTypeMismatchTip = "文件类型不匹配"
 singleFileMaxSize = 5242880
 singleFileMaxSizeTip = "图片最大不超过5M!"
 allFilesMaxSize = 10485760
 allFilesMaxSizeTip = "总图片大小不超过10M!"//单选条件下无效,只做单个图片大小判断
 fileCondition = object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (fileType == FileType.IMAGE && uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 }
 }
}
mFileSelector = FileSelector
 .with(this)
 .setRequestCode(REQUEST_CHOOSE_FILE)
 .setTypeMismatchTip("文件类型不匹配")
 .setMinCount(1, "至少选一个文件!")
 .setMaxCount(10, "最多选十个文件!")//单选条件下无效, 只做最少数量判断
 .setOverLimitStrategy(OVER_LIMIT_EXCEPT_OVERFLOW)
 .setSingleFileMaxSize(1048576, "大小不能超过1M!")//单选条件下无效, FileSelectOptions.singleFileMaxSize
 .setAllFilesMaxSize(10485760, "总大小不能超过10M!")//单选条件下无效,只做单个图片大小判断 setSingleFileMaxSize
 .setMimeTypes("image/*")//默认不做文件类型约束,不同类型系统提供的选择UI不一样 eg: arrayOf("video/*","audio/*","image/*")
 .applyOptions(optionsImage)
 //优先使用 FileSelectOptions 中设置的 FileSelectCondition
 .filter(object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return when (fileType) {
 FileType.IMAGE -> (uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 FileType.VIDEO -> false
 FileType.AUDIO -> false
 else -> false
 }
 }
 })
 .callback(object : FileSelectCallBack {
 override fun onSuccess(results: List<FileSelectResult>?) {
 ResultUtils.resetUI(mTvResult)
 if (results.isNullOrEmpty()) {
 toastLong("没有选取文件")
 return
 }
 showSelectResult(results)
 }
 override fun onError(e: Throwable?) {
 FileLogger.e("FileSelectCallBack onError ${e?.message}")
 ResultUtils.setErrorText(mTvError, e)
 }
 })
 .choose()

2. 多选图片(多选+单一类型)

val optionsImage = FileSelectOptions().apply {
 fileType = FileType.IMAGE
 fileTypeMismatchTip = "文件类型不匹配"
 singleFileMaxSize = 5242880
 singleFileMaxSizeTip = "单张图片最大不超过5M!"
 allFilesMaxSize = 10485760
 allFilesMaxSizeTip = "图片总大小不超过10M!"
 fileCondition = object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (fileType == FileType.IMAGE && uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 }
 }
}
mFileSelector = FileSelector
 .with(this)
 .setRequestCode(REQUEST_CHOOSE_FILE)
 .setMultiSelect()//默认是单选false
 .setMinCount(1, "至少选一个文件!")
 .setMaxCount(2, "最多选两个文件!")
 //优先使用 FileSelectOptions.singleFileMaxSize , 单位 Byte
 .setSingleFileMaxSize(3145728, "单个大小不能超过3M!")
 .setAllFilesMaxSize(20971520, "总文件大小不能超过20M!")
 //1. 文件超过数量限制或大小限制
 //2. 单一类型: 保留未超限制的文件并返回, 去掉后面溢出的部分; 多种类型: 保留正确的文件, 去掉错误类型的所有文件
 .setOverLimitStrategy(this.mOverLimitStrategy)
 .setMimeTypes("image/*")//默认不做文件类型约束,不同类型系统提供的选择UI不一样 eg: arrayOf("video/*","audio/*","image/*")
 .applyOptions(optionsImage)
 //优先使用 FileSelectOptions 中设置的 FileSelectCondition
 .filter(object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (fileType == FileType.IMAGE) && (uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 }
 })
 .callback(object : FileSelectCallBack {
 override fun onSuccess(results: List<FileSelectResult>?) {
 FileLogger.w("FileSelectCallBack onSuccess ${results?.size}")
 mAdapter.setData(null)
 if (results.isNullOrEmpty()) {
 toastLong("没有选取文件")
 return
 }
 showSelectResult(results)
 }
 override fun onError(e: Throwable?) {
 FileLogger.e("FileSelectCallBack onError ${e?.message}")
 ResultUtils.setErrorText(mTvError, e)
 mAdapter.setData(null)
 mBtSelect.text = "$mShowText (0)"
 }
 })
 .choose()

3. 多选文件(多选+多种类型)

//图片
val optionsImage = FileSelectOptions().apply {
 fileType = FileType.IMAGE
 minCount = 1
 maxCount = 2
 minCountTip = "至少选择一张图片"
 maxCountTip = "最多选择两张图片"
 singleFileMaxSize = 5242880
 singleFileMaxSizeTip = "单张图片最大不超过5M!"
 allFilesMaxSize = 10485760
 allFilesMaxSizeTip = "图片总大小不超过10M!"
 fileCondition = object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (fileType == FileType.IMAGE && uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 }
 }
}
//音频
val optionsAudio = FileSelectOptions().apply {
 fileType = FileType.AUDIO
 minCount = 2
 maxCount = 3
 minCountTip = "至少选择两个音频文件"
 maxCountTip = "最多选择三个音频文件"
 singleFileMaxSize = 20971520
 singleFileMaxSizeTip = "单音频最大不超过20M!"
 allFilesMaxSize = 31457280
 allFilesMaxSizeTip = "音频总大小不超过30M!"
 fileCondition = object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (uri != null)
 }
 }
}
//文本文件 txt
val optionsTxt = FileSelectOptions().apply {
 fileType = FileType.TXT
 minCount = 1
 maxCount = 2
 minCountTip = "至少选择一个文本文件"
 maxCountTip = "最多选择两个文本文件"
 singleFileMaxSize = 5242880
 singleFileMaxSizeTip = "单文本文件最大不超过5M!"
 allFilesMaxSize = 10485760
 allFilesMaxSizeTip = "文本文件总大小不超过10M!"
 fileCondition = object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return (uri != null)
 }
 }
}
/*
 注:如果某个FileSelectOptions没通过限定条件, 则该FileSelectOptions不会返回
 eg: 采用上面的限制条件下,图片、音频、文本文件各选一个, 因为音频最小数量设定为`2`不满足设定条件则去除所有音频选择结果
 , 所以返回结果中只有图片和文本文件(限于OVER_LIMIT_EXCEPT_OVERFLOW)
 */
mFileSelector = FileSelector
 .with(this)
 .setRequestCode(REQUEST_CHOOSE_FILE)
 .setMultiSelect()//默认是单选false
 /*
 实际最少数量限制为 setMinCount 和 (optionsImage.minCount + optionsAudio.minCount +...) 中的最小值
 实际最大数量限制为 setMaxCount 和 (optionsImage.maxCount + optionsAudio.maxCount +...) 中的最大值, 所以此处的最大值限制是无效的
 */
 .setMinCount(1, "设定类型文件至少选择一个!")
 .setMaxCount(4, "最多选四个文件!")
 /*
 实际单文件大小限制为 setSingleFileMaxSize 和 (optionsImage.singleFileMaxSize + optionsAudio.singleFileMaxSize +...) 中的最小值
 实际总大小限制为 setAllFilesMaxSize 和 (optionsImage.allFilesMaxSize + optionsAudio.allFilesMaxSize +...) 中的最大值
 */
 // 优先使用 `自定义FileSelectOptions` 中设置的单文件大小限制, 如果没有设置则采用该值
 .setSingleFileMaxSize(2097152, "单文件大小不能超过2M!")
 .setAllFilesMaxSize(52428800, "总文件大小不能超过50M!")
 //1. 文件超过数量限制或大小限制
 //2. 单一类型: 保留未超限制的文件并返回, 去掉后面溢出的部分; 多种类型: 保留正确的文件, 去掉错误类型的所有文件
 .setOverLimitStrategy(this.mOverLimitStrategy)
 //eg: ando.file.core.FileMimeType
 .setMimeTypes(arrayOf("audio/*", "image/*", "text/plain"))//同"*/*",默认不做文件类型约束, 不同类型系统提供的选择UI不一样 eg: arrayOf("video/*","audio/*","image/*")
 //如果setMimeTypes和applyOptions没对应上会出现`文件类型不匹配问题`
 .applyOptions(optionsImage, optionsAudio, optionsTxt)
 //优先使用 FileSelectOptions 中设置的 FileSelectCondition
 .filter(object : FileSelectCondition {
 override fun accept(fileType: FileType, uri: Uri?): Boolean {
 return when (fileType) {
 FileType.IMAGE -> (uri != null && !uri.path.isNullOrBlank() && !FileUtils.isGif(uri))
 FileType.AUDIO -> true
 FileType.TXT -> true
 else -> false
 }
 }
 })
 .callback(object : FileSelectCallBack {
 override fun onSuccess(results: List<FileSelectResult>?) {
 FileLogger.w("FileSelectCallBack onSuccess ${results?.size}")
 mAdapter.setData(null)
 if (results.isNullOrEmpty()) {
 toastLong("没有选取文件")
 return
 }
 showSelectResult(results)
 }
 override fun onError(e: Throwable?) {
 FileLogger.e("FileSelectCallBack onError ${e?.message}")
 ResultUtils.setErrorText(mTvError, e)
 mAdapter.setData(null)
 mBtSelect.text = "$mShowText (0)"
 }
 })
 .choose()

4.压缩图片 ImageCompressor.kt

方式一 直接压缩不缓存(Direct compression without caching)

val bitmap:Bitmap=ImageCompressEngine.compressPure(uri)

方式二 压缩图片并缓存(Compress pictures and cache)

/**
 * 压缩图片 1.Luban算法; 2.直接压缩 -> val bitmap:Bitmap=ImageCompressEngine.compressPure(uri)
 *
 * T : String.filePath / Uri / File
 */
fun <T> compressImage(context: Context, photos: List<T>, success: (index: Int, uri: Uri?) -> Unit) {
 ImageCompressor
 .with(context)
 .load(photos)
 .ignoreBy(100)//单位 Byte
 .setTargetDir(getCompressedImageCacheDir())
 .setFocusAlpha(false)
 .enableCache(true)
 .filter(object : ImageCompressPredicate {
 override fun apply(uri: Uri?): Boolean {
 //FileLogger.i("compressImage predicate $uri ${FileUri.getFilePathByUri(uri)}")
 return if (uri != null) !FileUtils.getExtension(uri).endsWith("gif") else false
 }
 })
 .setRenameListener(object : OnImageRenameListener {
 override fun rename(uri: Uri?): String? {
 try {
 val filePath = FileUri.getFilePathByUri(uri)
 val md = MessageDigest.getInstance("MD5")
 md.update(filePath?.toByteArray() ?: return "")
 return BigInteger(1, md.digest()).toString(32)
 } catch (e: NoSuchAlgorithmException) {
 e.printStackTrace()
 }
 return ""
 }
 })
 .setImageCompressListener(object : OnImageCompressListener {
 override fun onStart() {}
 override fun onSuccess(index: Int, uri: Uri?) {
 success.invoke(index, uri)
 }
 override fun onError(e: Throwable?) {
 FileLogger.e("compressImage onError ${e?.message}")
 }
 }).launch()
}

文件操作工具类(File operation tools)

1. 获取文件MimeType类型👉FileMimeType.kt

根据File Name/Path/Url获取相应MimeType

fun getMimeType(str: String?): String {...}
fun getMimeType(uri: Uri?): String {...}
//MimeTypeMap.getSingleton().getMimeTypeFromExtension(...) 的补充
fun getMimeTypeSupplement(fileName: String): String {...}

2. 计算文件或文件夹的大小👉FileSizeUtils.kt

获取指定文件/文件夹大小(Get the size of the specified file folder)

@Throws(Exception::class)
fun getFolderSize(file: File?): Long {
 var size = 0L
 if (file == null || !file.exists()) return size
 val files = file.listFiles()
 if (files.isNullOrEmpty()) return size
 for (i in files.indices) {
 size += if (files[i].isDirectory) getFolderSize(files[i]) else getFileSize(files[i])
 }
 return size
}

获取文件大小(Get file size)

fun getFileSize(file: File?): Long{...}
fun getFileSize(uri: Uri?): Long{...}

自动计算指定文件/文件夹大小(Automatically calculate the size of the specified file folder)

fun getFileOrDirSizeFormatted(path: String?): String {}...}

格式化大小(BigDecimal实现)

/**
 * @param scale 精确到小数点以后几位 (Accurate to a few decimal places)
 */
fun formatFileSize(size: Long, scale: Int, withUnit: Boolean = false): String {
 val divisor = 1024L
 //ROUND_DOWN 1023 -> 1023B ; ROUND_HALF_UP 1023 -> 1KB
 val kiloByte: BigDecimal = formatSizeByTypeWithDivisor(BigDecimal.valueOf(size), scale, SIZE_TYPE_B, divisor)
 if (kiloByte.toDouble() < 1) {
 return "${kiloByte.toPlainString()}${if (withUnit) SIZE_TYPE_B.unit else ""}"
 }
 //KB
 val megaByte = formatSizeByTypeWithDivisor(kiloByte, scale, SIZE_TYPE_KB, divisor)
 if (megaByte.toDouble() < 1) {
 return "${kiloByte.toPlainString()}${if (withUnit) SIZE_TYPE_KB.unit else ""}"
 }
 //M
 val gigaByte = formatSizeByTypeWithDivisor(megaByte, scale, SIZE_TYPE_MB, divisor)
 if (gigaByte.toDouble() < 1) {
 return "${megaByte.toPlainString()}${if (withUnit) SIZE_TYPE_MB.unit else ""}"
 }
 //GB
 val teraBytes = formatSizeByTypeWithDivisor(gigaByte, scale, SIZE_TYPE_GB, divisor)
 if (teraBytes.toDouble() < 1) {
 return "${gigaByte.toPlainString()}${if (withUnit) SIZE_TYPE_GB.unit else ""}"
 }
 //TB
 return "${teraBytes.toPlainString()}${if (withUnit) SIZE_TYPE_TB.unit else ""}"
}

//scale 精确到小数点以后几位
fun formatSizeByTypeWithoutUnit(size: BigDecimal, scale: Int, sizeType: FileSizeType): BigDecimal =
 size.divide(
 BigDecimal.valueOf(when (sizeType) {
 SIZE_TYPE_B -> 1L
 SIZE_TYPE_KB -> 1024L
 SIZE_TYPE_MB -> 1024L * 1024L
 SIZE_TYPE_GB -> 1024L * 1024L * 1024L
 SIZE_TYPE_TB -> 1024L * 1024L * 1024L * 1024L
 }),
 scale,
 //ROUND_DOWN 1023 -> 1023B ; ROUND_HALF_UP 1023 -> 1KB
 if (sizeType == SIZE_TYPE_B) BigDecimal.ROUND_DOWN else BigDecimal.ROUND_HALF_UP
 )

fun formatSizeByTypeWithUnit(size: Long, scale: Int, sizeType: FileSizeType): String {
 return "${formatSizeByTypeWithoutUnit(size.toBigDecimal(), scale, sizeType).toPlainString()}${sizeType.unit}"
}

3. 直接打开Url/Uri(远程or本地)👉FileOpener.kt

打开系统分享弹窗(Open the system sharing popup)

fun openShare(context: Context, uri: Uri, title: String = "分享文件") {
 val intent = Intent(Intent.ACTION_SEND)
 intent.putExtra(Intent.EXTRA_STREAM, uri)
 intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION)
 // Put the Uri and MIME type in the result Intent
 intent.setDataAndType(uri, getMimeType(uri))
 context.startActivity(Intent.createChooser(intent, title))
}

打开浏览器(Open browser)

@SuppressLint("QueryPermissionsNeeded")
fun openBrowser(
 context: Context, url: String, title: String = "请选择浏览器", newTask: Boolean = false,
 block: ((result: Boolean, msg: String?) -> Unit)? = null,
) {
 try {
 val intent = Intent(Intent.ACTION_VIEW)
 intent.data = Uri.parse(url)
 if (newTask) {
 intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
 }
 //startActivity(intent)
 //https://developer.android.com/about/versions/11/privacy/package-visibility
 if (intent.resolveActivity(context.packageManager) != null) {
 context.startActivity(Intent.createChooser(intent, title))
 block?.invoke(true, null)
 } else {
 block?.invoke(true, "没有可用浏览器")
 }
 } catch (e: ActivityNotFoundException) {
 e.printStackTrace()
 block?.invoke(true, e.toString())
 }
}

直接打开Url对应的系统应用

fun openUrl(activity: Activity, url: String?) {
 try {
 val intent = Intent(Intent.ACTION_VIEW)
 intent.setDataAndType(Uri.parse(url), getMimeType(url))
 activity.startActivity(intent)
 } catch (e: Exception) {
 FileLogger.e("openUrl error : " + e.message)
 }
}

根据文件路径和类型(后缀判断)显示支持该格式的程序

fun openFileBySystemChooser(context: Any, uri: Uri?, mimeType: String? = null) =
 uri?.let { u ->
 Intent.createChooser(createOpenFileIntent(u, mimeType), "选择程序")?.let {
 startActivity(context, it)
 }
 }

选择文件【调用系统的文件管理】

/**
 * ### 选择文件【调用系统的文件管理】 (Select file [call system file management])
 *
 * 注:
 *
 * 1. Intent.setType 不能为空(Can not be empty) !
 *
 * 2. mimeTypes 会覆盖(Will overwrite) mimeType
 *
 * 3. ACTION_GET_CONTENT, ACTION_OPEN_DOCUMENT 效果相同, Android Q 上使用 `ACTION_GET_CONTENT` 会出现:
 * ```
 * java.lang.SecurityException: UID 10483 does not have permission to content://com.android.providers.media.documents/document/image%3A16012 [user 0];
 * you could obtain access using ACTION_OPEN_DOCUMENT or related APIs
 * ```
 *
 * 4. 开启多选(Open multiple selection) resultCode = -1
 */
fun createChooseIntent(mimeType: String?, mimeTypes: Array<String>?, multiSelect: Boolean): Intent =
 /*
 * 隐式允许用户选择一种特定类型的数据。
 * Implicitly allow the user to select a particular kind of data.
 *
 * Same as : ACTION_GET_CONTENT , ACTION_OPEN_DOCUMENT
 */
 Intent(Intent.ACTION_OPEN_DOCUMENT).apply {
 putExtra(Intent.EXTRA_ALLOW_MULTIPLE, multiSelect)
 //"file/*"比"*/*"少了一些侧边栏选项
 //"file" has fewer sidebar options than "*/*"
 if (mimeType.isNullOrBlank() && mimeTypes.isNullOrEmpty()) type = "*/*"
 else {
 type = if (mimeType.isNullOrEmpty()) "*/*" else mimeType
 putExtra(Intent.EXTRA_MIME_TYPES, mimeTypes)
 }
 // Only return URIs that can be opened with ContentResolver
 addCategory(Intent.CATEGORY_OPENABLE)
 }

4. 获取文件Uri/Path👉FileUri.kt

从File路径中获取Uri

fun getUriByPath(path: String?): Uri? = if (path.isNullOrBlank()) null else getUriByFile(File(path))
fun getUriByFile(file: File?): Uri? =
 file?.let {
 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
 val authority = FileOperator.getContext().packageName + PATH_SUFFIX
 FileProvider.getUriForFile(FileOperator.getContext(), authority, file)
 } else Uri.fromFile(file)
 }

获取Uri对应的文件路径,兼容API 26

fun getFilePathByUri(context: Context?, uri: Uri?): String? {
 if (context == null || uri == null) return null
 val scheme = uri.scheme
 // 以 file:// 开头的使用第三方应用打开
 if (ContentResolver.SCHEME_FILE.equals(scheme, ignoreCase = true)) return uri.path
 return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) getPath(context, uri) else getPathKitkat(context, uri)
}

5. 通用文件工具类👉FileUtils.kt

eg :boolean copyFile = FileUtils.copyFile(fileOld, "/test_" + i,
 getExternalFilesDir(null).getPath());
File fileNew =new File(getExternalFilesDir(null).getPath() +"/"+ "test_" + i);

注意(Note)

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
 super.onActivityResult(requestCode, resultCode, data)
 //选择结果交给 FileSelector 处理, 可通过`requestCode -> REQUEST_CHOOSE_FILE`进行区分
 mFileSelector?.obtainResult(requestCode, resultCode, data)
}

v1.1.0

1.增加文件类型不匹配判断;
2.开启多选: FileSelector.setSelectMode(true) 改为 setMultiSelect() , 默认为单选模式
3.增加清理压缩图片缓存方法
4.单选 setMinCount 提示问题
5.修改`FileSizeUtils.kt`算法
6.FileSelectResult 加入MimeType
7.多选图片和多选文件改为RecyclerView进行结果展示
8.增加数量限制
9.增加更多注释, 重要注释为汉英双译
10.增加 LICENSE
11.修复了一些BUG

Fiexd Bug

1.Invalid image: ExifInterface got an unsupported image format

W/ExifInterface: Invalid image: ExifInterface got an unsupported image format
 file(ExifInterface supports JPEG and some RAW image formats only) or a corrupted JPEG file to ExifInterface.
 java.io.IOException: Invalid byte order: 0
 at android.media.ExifInterface.readByteOrder(ExifInterface.java:3134)
 at android.media.ExifInterface.isOrfFormat(ExifInterface.java:2449)
 at android.media.ExifInterface.getMimeType(ExifInterface.java:2327)
 at android.media.ExifInterface.loadAttributes(ExifInterface.java:1755)
 at android.media.ExifInterface.<init>(ExifInterface.java:1449)
 ...
Fixed :
 dependencies {
 compileOnly "androidx.exifinterface:exifinterface:1.3.2"
 ...
 }
 Then replace `android.media.ExifInterface` with `androidx.exifinterface.media.ExifInterface`

2.ImageDecoder$DecodeException: Failed to create image decoder with message

Caused by: android.graphics.ImageDecoder$DecodeException:
Failed to create image decoder with message 'unimplemented'Input contained an error.

3.SecurityException... you could obtain access using ACTION_OPEN_DOCUMENT or related APIs

java.lang.SecurityException: UID 10483 does not have permission to
 content://com.android.providers.media.documents/document/image%3A16012 [user 0];
 you could obtain access using ACTION_OPEN_DOCUMENT or related APIs

4.IllegalArgumentException: column '_data' does not exist

参考(Reference)

Google

感谢(Thanks)

其它(Other)

许可(LICENSE)

Copyright 2019 javakam, FileOperator Open Source Project
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.