Implement storage files in Java

This change implements storage files in java to remove the dependencies
on JNI.

Bug: 352078117
Test: atest aconfig_storage_file.test.java

Change-Id: I34438576d09d0aa31eabc60f472e71cebf1552a0

tools/aconfig/aconfig_storage_file/tests/srcs/FlagTableTest.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2024 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 android.aconfig.storage.test;
+
+import static org.junit.Assert.assertEquals;
+
+import android.aconfig.storage.FileType;
+import android.aconfig.storage.FlagTable;
+import android.aconfig.storage.FlagType;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class FlagTableTest {
+
+    @Test
+    public void testFlagTable_rightHeader() throws Exception {
+        FlagTable flagTable = FlagTable.fromBytes(TestDataUtils.getTestFlagMapByteBuffer());
+        FlagTable.Header header = flagTable.getHeader();
+        assertEquals(1, header.getVersion());
+        assertEquals("mockup", header.getContainer());
+        assertEquals(FileType.FLAG_MAP, header.getFileType());
+        assertEquals(321, header.getFileSize());
+        assertEquals(8, header.getNumFlags());
+        assertEquals(31, header.getBucketOffset());
+        assertEquals(99, header.getNodeOffset());
+    }
+
+    @Test
+    public void testFlagTable_rightNode() throws Exception {
+        FlagTable flagTable = FlagTable.fromBytes(TestDataUtils.getTestFlagMapByteBuffer());
+
+        FlagTable.Node node1 = flagTable.get(0, "enabled_ro");
+        FlagTable.Node node2 = flagTable.get(0, "enabled_rw");
+        FlagTable.Node node3 = flagTable.get(2, "enabled_rw");
+        FlagTable.Node node4 = flagTable.get(1, "disabled_rw");
+        FlagTable.Node node5 = flagTable.get(1, "enabled_fixed_ro");
+        FlagTable.Node node6 = flagTable.get(1, "enabled_ro");
+        FlagTable.Node node7 = flagTable.get(2, "enabled_fixed_ro");
+        FlagTable.Node node8 = flagTable.get(0, "disabled_rw");
+
+        assertEquals("enabled_ro", node1.getFlagName());
+        assertEquals("enabled_rw", node2.getFlagName());
+        assertEquals("enabled_rw", node3.getFlagName());
+        assertEquals("disabled_rw", node4.getFlagName());
+        assertEquals("enabled_fixed_ro", node5.getFlagName());
+        assertEquals("enabled_ro", node6.getFlagName());
+        assertEquals("enabled_fixed_ro", node7.getFlagName());
+        assertEquals("disabled_rw", node8.getFlagName());
+
+        assertEquals(0, node1.getPackageId());
+        assertEquals(0, node2.getPackageId());
+        assertEquals(2, node3.getPackageId());
+        assertEquals(1, node4.getPackageId());
+        assertEquals(1, node5.getPackageId());
+        assertEquals(1, node6.getPackageId());
+        assertEquals(2, node7.getPackageId());
+        assertEquals(0, node8.getPackageId());
+
+        assertEquals(FlagType.ReadOnlyBoolean, node1.getFlagType());
+        assertEquals(FlagType.ReadWriteBoolean, node2.getFlagType());
+        assertEquals(FlagType.ReadWriteBoolean, node3.getFlagType());
+        assertEquals(FlagType.ReadWriteBoolean, node4.getFlagType());
+        assertEquals(FlagType.FixedReadOnlyBoolean, node5.getFlagType());
+        assertEquals(FlagType.ReadOnlyBoolean, node6.getFlagType());
+        assertEquals(FlagType.FixedReadOnlyBoolean, node7.getFlagType());
+        assertEquals(FlagType.ReadWriteBoolean, node8.getFlagType());
+
+        assertEquals(1, node1.getFlagIndex());
+        assertEquals(2, node2.getFlagIndex());
+        assertEquals(1, node3.getFlagIndex());
+        assertEquals(0, node4.getFlagIndex());
+        assertEquals(1, node5.getFlagIndex());
+        assertEquals(2, node6.getFlagIndex());
+        assertEquals(0, node7.getFlagIndex());
+        assertEquals(0, node8.getFlagIndex());
+
+        assertEquals(-1, node1.getNextOffset());
+        assertEquals(151, node2.getNextOffset());
+        assertEquals(-1, node3.getNextOffset());
+        assertEquals(-1, node4.getNextOffset());
+        assertEquals(236, node5.getNextOffset());
+        assertEquals(-1, node6.getNextOffset());
+        assertEquals(-1, node7.getNextOffset());
+        assertEquals(-1, node8.getNextOffset());
+    }
+}