[Feature] Lower minSdkVersion to 15.

Author: zhanghai

generate.sh

@@ -14,7 +14,8 @@ cp -r "${SDK_JAVA_SOURCE_ROOT}/java/nio/file" "${LIBRARY_JAVA_SOURCE_ROOT}/java8
 find "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file" -iname '*.java' -type f -print0 | xargs -0 sed -Ei \
 -e 's/java\.nio\.file/java8.nio.file/g' \
 -e 's/java\.time/org.threeten.bp/g' \
--e 's/\bMath(\.floor(Div|Mod))/org.threeten.bp.jdk8.Jdk8Methods\1/g' \
+-e 's/\bMath(\.floor(Div|Mod))\b/org.threeten.bp.jdk8.Jdk8Methods\1/g' \
+-e 's/\bObjects(\.requireNonNull)\b/org.threeten.bp.jdk8.Jdk8Methods\1/g' \
 -e 's/java(\.util\.(Spliterator|function|stream))/java9\1/g' \
 -e '/^\s*import(\s+static)?\s+sun\..+\s*;\s*$/d' \
 
@@ -253,6 +254,16 @@ find "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file" -iname '*.java' -type f -print
 -e "s/java(\.nio\.channels\.(File|SeekableByte)Channel)/java8\1/g" \
 -e "/^\s*import\s+java\.nio\.channels\.\*\s*;\s*$/a\import java8.nio.channels.FileChannel;\nimport java8.nio.channels.SeekableByteChannel;"
 
+mkdir -p "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/charset"
+rm -rf "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/charset"
+mkdir "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/charset"
+cp "${SDK_JAVA_SOURCE_ROOT}/java/nio/charset/StandardCharsets.java" "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/charset/StandardCharsets.java"
+sed -Ei \
+-e "s/^(\s*package\s+)java(\.nio\.charset\s*;\s*)$/\1java8\2\n\nimport java.nio.charset.*;/" \
+"${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/charset/StandardCharsets.java"
+find "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file" -iname '*.java' -type f -print0 | xargs -0 sed -Ei \
+-e 's/\bjava(\.nio\.charset\.StandardCharsets)\b/java8\1/g'
+
 mkdir -p "${LIBRARY_JAVA_SOURCE_ROOT}/java8/io"
 rm -rf "${LIBRARY_JAVA_SOURCE_ROOT}/java8/io"
 mkdir "${LIBRARY_JAVA_SOURCE_ROOT}/java8/io"
@@ -368,6 +379,21 @@ find "${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file" -iname '*.java' -type f -print
 -e "s/\b([A-Za-z][A-Za-z0-9_]*)\.lines\(\)/java8.io.BufferedReaders.lines(\1)/g"
 
 git apply <<EOF
+diff --git a/library/src/main/java/java8/nio/file/DirectoryIteratorException.java b/library/src/main/java/java8/nio/file/DirectoryIteratorException.java
+index 7356794..fd0d53d 100644
+--- a/library/src/main/java/java8/nio/file/DirectoryIteratorException.java
++++ b/library/src/main/java/java8/nio/file/DirectoryIteratorException.java
+@@ -56,7 +56,9 @@ public final class DirectoryIteratorException
+ * if the cause is {@code null}
+ */
+ public DirectoryIteratorException(IOException cause) {
+- super(org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(cause));
++ super(org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(cause).toString());
++
++ initCause(cause);
+ }
+ 
+ /**
 diff --git a/${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file/FileSystems.java b/${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file/FileSystems.java
 index 432f013..cfdaacb 100644
 --- a/${LIBRARY_JAVA_SOURCE_ROOT}/java8/nio/file/FileSystems.java

library/build.gradle

@@ -4,7 +4,7 @@ android {
  compileSdkVersion 28
  buildToolsVersion '28.0.3'
  defaultConfig {
- minSdkVersion 21
+ minSdkVersion 15
  targetSdkVersion 28
  versionCode 1
  versionName '1.0.0'
@@ -23,6 +23,6 @@ android {
 
 dependencies {
  implementation fileTree(dir: 'libs', include: ['*.jar'])
- implementation 'com.jakewharton.threetenabp:threetenabp:1.1.1'
- implementation 'net.sourceforge.streamsupport:android-retrostreams:1.7.0'
+ api 'com.jakewharton.threetenabp:threetenabp:1.1.1'
+ api 'net.sourceforge.streamsupport:android-retrostreams:1.7.0'
 }

library/src/main/java/java8/nio/charset/StandardCharsets.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package java8.nio.charset;
+
+import java.nio.charset.*;
+
+/**
+ * Constant definitions for the standard {@link Charset Charsets}. These
+ * charsets are guaranteed to be available on every implementation of the Java
+ * platform.
+ *
+ * @see <a href="Charset#standard">Standard Charsets</a>
+ * @since 1.7
+ */
+public final class StandardCharsets {
+
+ private StandardCharsets() {
+ throw new AssertionError("No java.nio.charset.StandardCharsets instances for you!");
+ }
+ /**
+ * Seven-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the
+ * Unicode character set
+ */
+ public static final Charset US_ASCII = Charset.forName("US-ASCII");
+ /**
+ * ISO Latin Alphabet No. 1, a.k.a. ISO-LATIN-1
+ */
+ public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");
+ /**
+ * Eight-bit UCS Transformation Format
+ */
+ public static final Charset UTF_8 = Charset.forName("UTF-8");
+ /**
+ * Sixteen-bit UCS Transformation Format, big-endian byte order
+ */
+ public static final Charset UTF_16BE = Charset.forName("UTF-16BE");
+ /**
+ * Sixteen-bit UCS Transformation Format, little-endian byte order
+ */
+ public static final Charset UTF_16LE = Charset.forName("UTF-16LE");
+ /**
+ * Sixteen-bit UCS Transformation Format, byte order identified by an
+ * optional byte-order mark
+ */
+ public static final Charset UTF_16 = Charset.forName("UTF-16");
+}

library/src/main/java/java8/nio/file/DirectoryIteratorException.java

@@ -56,7 +56,9 @@ public final class DirectoryIteratorException
  * if the cause is {@code null}
  */
  public DirectoryIteratorException(IOException cause) {
- super(Objects.requireNonNull(cause));
+ super(org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(cause).toString());
+
+ initCause(cause);
  }
 
  /**

library/src/main/java/java8/nio/file/Files.java

@@ -43,7 +43,7 @@
 import java.nio.charset.Charset;
 import java.nio.charset.CharsetDecoder;
 import java.nio.charset.CharsetEncoder;
-import java.nio.charset.StandardCharsets;
+import java8.nio.charset.StandardCharsets;
 import java8.nio.file.attribute.BasicFileAttributeView;
 import java8.nio.file.attribute.BasicFileAttributes;
 import java8.nio.file.attribute.DosFileAttributes; // javadoc
@@ -849,7 +849,7 @@ public static Path createTempFile(Path dir,
  FileAttribute<?>... attrs)
  throws IOException
  {
- return TempFileHelper.createTempFile(Objects.requireNonNull(dir),
+ return TempFileHelper.createTempFile(org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(dir),
  prefix, suffix, attrs);
  }
 
@@ -947,7 +947,7 @@ public static Path createTempDirectory(Path dir,
  FileAttribute<?>... attrs)
  throws IOException
  {
- return TempFileHelper.createTempDirectory(Objects.requireNonNull(dir),
+ return TempFileHelper.createTempDirectory(org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(dir),
  prefix, attrs);
  }
 
@@ -2673,7 +2673,7 @@ public static Path walkFileTree(Path start,
  throw new AssertionError("Should not get here");
  }
 
- if (Objects.requireNonNull(result) != FileVisitResult.CONTINUE) {
+ if (org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(result) != FileVisitResult.CONTINUE) {
  if (result == FileVisitResult.TERMINATE) {
  break;
  } else if (result == FileVisitResult.SKIP_SIBLINGS) {
@@ -2958,7 +2958,7 @@ public static long copy(InputStream in, Path target, CopyOption... options)
  throws IOException
  {
  // ensure not null before opening file
- Objects.requireNonNull(in);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(in);
 
  // check for REPLACE_EXISTING
  boolean replaceExisting = false;
@@ -3040,7 +3040,7 @@ public static long copy(InputStream in, Path target, CopyOption... options)
  */
  public static long copy(Path source, OutputStream out) throws IOException {
  // ensure not null before opening file
- Objects.requireNonNull(out);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(out);
 
  try (InputStream in = newInputStream(source)) {
  return copy(in, out);
@@ -3264,7 +3264,7 @@ public static Path write(Path path, byte[] bytes, OpenOption... options)
  throws IOException
  {
  // ensure bytes is not null before opening file
- Objects.requireNonNull(bytes);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(bytes);
 
  try (OutputStream out = Files.newOutputStream(path, options)) {
  int len = bytes.length;
@@ -3323,7 +3323,7 @@ public static Path write(Path path, Iterable<? extends CharSequence> lines,
  throws IOException
  {
  // ensure lines is not null before opening file
- Objects.requireNonNull(lines);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(lines);
  CharsetEncoder encoder = cs.newEncoder();
  OutputStream out = newOutputStream(path, options);
  try (BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out, encoder))) {

library/src/main/java/java8/nio/file/SimpleFileVisitor.java

@@ -57,8 +57,8 @@ protected SimpleFileVisitor() {
  public FileVisitResult preVisitDirectory(T dir, BasicFileAttributes attrs)
  throws IOException
  {
- Objects.requireNonNull(dir);
- Objects.requireNonNull(attrs);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(dir);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(attrs);
  return FileVisitResult.CONTINUE;
  }
 
@@ -72,8 +72,8 @@ public FileVisitResult preVisitDirectory(T dir, BasicFileAttributes attrs)
  public FileVisitResult visitFile(T file, BasicFileAttributes attrs)
  throws IOException
  {
- Objects.requireNonNull(file);
- Objects.requireNonNull(attrs);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(file);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(attrs);
  return FileVisitResult.CONTINUE;
  }
 
@@ -87,7 +87,7 @@ public FileVisitResult visitFile(T file, BasicFileAttributes attrs)
  public FileVisitResult visitFileFailed(T file, IOException exc)
  throws IOException
  {
- Objects.requireNonNull(file);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(file);
  throw exc;
  }
 
@@ -104,7 +104,7 @@ public FileVisitResult visitFileFailed(T file, IOException exc)
  public FileVisitResult postVisitDirectory(T dir, IOException exc)
  throws IOException
  {
- Objects.requireNonNull(dir);
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(dir);
  if (exc != null)
  throw exc;
  return FileVisitResult.CONTINUE;

library/src/main/java/java8/nio/file/attribute/FileTime.java

@@ -93,7 +93,7 @@ private FileTime(long value, TimeUnit unit, Instant instant) {
  * @return a {@code FileTime} representing the given value
  */
  public static FileTime from(long value, TimeUnit unit) {
- Objects.requireNonNull(unit, "unit");
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(unit, "unit");
  return new FileTime(value, unit, null);
  }
 
@@ -121,7 +121,7 @@ public static FileTime fromMillis(long value) {
  * @since 1.8
  */
  public static FileTime from(Instant instant) {
- Objects.requireNonNull(instant, "instant");
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(instant, "instant");
  return new FileTime(0, null, instant);
  }
 
@@ -139,7 +139,7 @@ public static FileTime from(Instant instant) {
  * since the epoch (1970-01-01T00:00:00Z); can be negative
  */
  public long to(TimeUnit unit) {
- Objects.requireNonNull(unit, "unit");
+ org.threeten.bp.jdk8.Jdk8Methods.requireNonNull(unit, "unit");
  if (this.unit != null) {
  return unit.convert(this.value, this.unit);
  } else {