Remove one method class in crypto package

PiperOrigin-RevId: 402787577

library/core/src/main/java/com/google/android/exoplayer2/upstream/crypto/AesCipherDataSink.java

@@ -66,10 +66,12 @@ public final class AesCipherDataSink implements DataSink {
   @Override
   public void open(DataSpec dataSpec) throws IOException {
     wrappedDataSink.open(dataSpec);
-    long nonce = CryptoUtil.getFNV64Hash(dataSpec.key);
     cipher =
         new AesFlushingCipher(
-            Cipher.ENCRYPT_MODE, secretKey, nonce, dataSpec.uriPositionOffset + dataSpec.position);
+            Cipher.ENCRYPT_MODE,
+            secretKey,
+            dataSpec.key,
+            dataSpec.uriPositionOffset + dataSpec.position);
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/upstream/crypto/AesCipherDataSource.java

@@ -51,10 +51,12 @@ public final class AesCipherDataSource implements DataSource {
   @Override
   public long open(DataSpec dataSpec) throws IOException {
     long dataLength = upstream.open(dataSpec);
-    long nonce = CryptoUtil.getFNV64Hash(dataSpec.key);
     cipher =
         new AesFlushingCipher(
-            Cipher.DECRYPT_MODE, secretKey, nonce, dataSpec.uriPositionOffset + dataSpec.position);
+            Cipher.DECRYPT_MODE,
+            secretKey,
+            dataSpec.key,
+            dataSpec.uriPositionOffset + dataSpec.position);
     return dataLength;
   }
 

library/core/src/main/java/com/google/android/exoplayer2/upstream/crypto/AesFlushingCipher.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.upstream.crypto;
 
+import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 import java.nio.ByteBuffer;
@@ -42,6 +43,10 @@ public final class AesFlushingCipher {
 
   private int pendingXorBytes;
 
+  public AesFlushingCipher(int mode, byte[] secretKey, @Nullable String nonce, long offset) {
+    this(mode, secretKey, getFNV64Hash(nonce), offset);
+  }
+
   public AesFlushingCipher(int mode, byte[] secretKey, long nonce, long offset) {
     try {
       cipher = Cipher.getInstance("AES/CTR/NoPadding");
@@ -121,4 +126,23 @@ public final class AesFlushingCipher {
   private byte[] getInitializationVector(long nonce, long counter) {
     return ByteBuffer.allocate(16).putLong(nonce).putLong(counter).array();
   }
+
+  /**
+   * Returns the hash value of the input as a long using the 64 bit FNV-1a hash function. The hash
+   * values produced by this function are less likely to collide than those produced by {@link
+   * #hashCode()}.
+   */
+  private static long getFNV64Hash(@Nullable String input) {
+    if (input == null) {
+      return 0;
+    }
+
+    long hash = 0;
+    for (int i = 0; i < input.length(); i++) {
+      hash ^= input.charAt(i);
+      // This is equivalent to hash *= 0x100000001b3 (the FNV magic prime number).
+      hash += (hash << 1) + (hash << 4) + (hash << 5) + (hash << 7) + (hash << 8) + (hash << 40);
+    }
+    return hash;
+  }
 }

library/core/src/main/java/com/google/android/exoplayer2/upstream/crypto/CryptoUtil.java

-/*
- * Copyright (C) 2016 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 com.google.android.exoplayer2.upstream.crypto;
-
-import androidx.annotation.Nullable;
-
-/** Utility functions for the crypto package. */
-/* package */ final class CryptoUtil {
-
-  private CryptoUtil() {}
-
-  /**
-   * Returns the hash value of the input as a long using the 64 bit FNV-1a hash function. The hash
-   * values produced by this function are less likely to collide than those produced by {@link
-   * #hashCode()}.
-   */
-  public static long getFNV64Hash(@Nullable String input) {
-    if (input == null) {
-      return 0;
-    }
-
-    long hash = 0;
-    for (int i = 0; i < input.length(); i++) {
-      hash ^= input.charAt(i);
-      // This is equivalent to hash *= 0x100000001b3 (the FNV magic prime number).
-      hash += (hash << 1) + (hash << 4) + (hash << 5) + (hash << 7) + (hash << 8) + (hash << 40);
-    }
-    return hash;
-  }
-}