Base 64 Kotlin extensions

api/current.txt

@@ -656,3 +656,15 @@ package androidx.core.widget {
 
 }
 
+package androidx.util {
+
+  public final class Base64Kt {
+    ctor public Base64Kt();
+    method public static String decodeBase64(kotlin.jvm.internal.StringCompanionObject, String input, int offset = "0", int len = "input.length", int flags = "Base64.DEFAULT", java.nio.charset.Charset byteArrayCharset = "Charsets.US_ASCII", java.nio.charset.Charset stringCharset = "Charsets.UTF_8");
+    method public static byte[] decodeBase64(byte[], int offset = "0", int len = "this.size", int flags = "Base64.DEFAULT");
+    method public static String encodeBase64(String, int offset = "0", int len = "this.length", int flags = "Base64.DEFAULT", java.nio.charset.Charset byteArrayCharset = "Charsets.US_ASCII", java.nio.charset.Charset stringCharset = "Charsets.UTF_8");
+    method public static byte[] encodeBase64(byte[], int offset = "0", int len = "this.size", int flags = "Base64.DEFAULT");
+  }
+
+}
+

src/androidTest/java/androidx/util/Base64Test.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2018 The Android 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.
+ */
+
+package androidx.util
+
+import android.util.Base64
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class Base64Test {
+    @Test fun toBase64String() {
+        val expected = "SGksIEphcmVk"
+        val actual = "Hi, Jared".encodeBase64(flags = Base64.NO_WRAP)
+        assertEquals(expected, actual)
+    }
+
+    @Test fun toBase64ByteArray() {
+        val expected = "AQIDBA=="
+        val actual = byteArrayOf(1, 2, 3, 4).encodeBase64(flags = Base64.NO_WRAP)
+            .toString(Charsets.UTF_8)
+        assertEquals(expected, actual)
+    }
+
+    @Test fun fromBase64String() {
+        val expected = "Hi, Jared"
+        val actual = String.decodeBase64("SGksIEphcmVk", flags = Base64.NO_WRAP)
+        assertEquals(expected, actual)
+    }
+
+    @Test fun fromBase64ByteArray() {
+        val expected = byteArrayOf(1, 2, 3, 4).toString(Charsets.UTF_8)
+        val actual = "AQIDBA==".toByteArray().decodeBase64(flags = Base64.NO_WRAP)
+            .toString(Charsets.UTF_8)
+        assertEquals(expected, actual)
+    }
+}

src/main/java/androidx/util/Base64.kt

@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2018 The Android 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.
+ */
+
+@file:Suppress("NOTHING_TO_INLINE")
+
+package androidx.util
+
+import android.util.Base64
+import java.nio.charset.Charset
+
+/**
+ * Convert [String] to base-64 encoded [String].
+ */
+inline fun String.encodeBase64(
+    offset: Int = 0,
+    len: Int = this.length,
+    flags: Int = Base64.DEFAULT,
+    byteArrayCharset: Charset = Charsets.US_ASCII,
+    stringCharset: Charset = Charsets.UTF_8
+): String = Base64.encode(toByteArray(byteArrayCharset), offset, len, flags).toString(stringCharset)
+
+/**
+ * Convert [ByteArray] to base-64 encoded [ByteArray].
+ */
+inline fun ByteArray.encodeBase64(
+    offset: Int = 0,
+    len: Int = this.size,
+    flags: Int = Base64.DEFAULT
+): ByteArray = Base64.encode(this, offset, len, flags)
+
+/**
+ * Convert base-64 encoded [String] to decoded [String].
+ */
+inline fun String.Companion.decodeBase64(
+    input: String,
+    offset: Int = 0,
+    len: Int = input.length,
+    flags: Int = Base64.DEFAULT,
+    byteArrayCharset: Charset = Charsets.US_ASCII,
+    stringCharset: Charset = Charsets.UTF_8
+): String =
+    Base64.decode(input.toByteArray(byteArrayCharset), offset, len, flags).toString(stringCharset)
+
+/**
+ * Convert base-64 encoded [ByteArray] to decoded [ByteArray].
+ */
+inline fun ByteArray.decodeBase64(
+    offset: Int = 0,
+    len: Int = this.size,
+    flags: Int = Base64.DEFAULT
+): ByteArray = Base64.decode(this, offset, len, flags)