extract method migrateV1toV2()

schildbach · Jul 31, 2024 · 7383f1d · 7383f1d
1 parent 626e5fb
commit 7383f1d
Showing 1 changed file with 38 additions and 34 deletions.
diff --git a/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java b/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java
@@ -97,6 +97,7 @@ protected boolean removeEldestEntry(Map.Entry<Sha256Hash, Object> entry) {
     // Used to stop other applications/processes from opening the store.
     protected FileLock fileLock = null;
     protected RandomAccessFile randomAccessFile = null;
+    private FileChannel channel;
     private int fileLength;
 
     /**
@@ -127,7 +128,7 @@ public SPVBlockStore(NetworkParameters params, File file, int capacity, boolean
 
             // Set up the backing file, empty if it doesn't exist.
             randomAccessFile = new RandomAccessFile(file, "rw");
-            FileChannel channel = randomAccessFile.getChannel();
+            channel = randomAccessFile.getChannel();
 
             // Lock the file.
             fileLock = channel.tryLock();
@@ -156,39 +157,8 @@ public SPVBlockStore(NetworkParameters params, File file, int capacity, boolean
 
             // Maybe migrate V1 to V2 format.
             if (Arrays.equals(HEADER_MAGIC_V1, currentHeader)) {
-                long currentLength = randomAccessFile.length();
-                long currentBlocksLength = currentLength - FILE_PROLOGUE_BYTES;
-                if (currentBlocksLength % RECORD_SIZE_V1 != 0)
-                    throw new BlockStoreException(
-                            "File size on disk indicates this is not a V1 block store: " + currentLength);
-                int currentCapacity = (int) (currentBlocksLength / RECORD_SIZE_V1);
-                log.info("Migrating SPV block chain file containing " + currentCapacity + " blocks from V1 to V2 " +
-                        "format: " + file);
-
-                randomAccessFile.setLength(fileLength);
-                // Map it into memory again because of the length change.
-                buffer.force();
-                buffer = channel.map(FileChannel.MapMode.READ_WRITE, 0, fileLength);
-
-                // migrate magic header
-                ((Buffer) buffer).rewind();
-                buffer.put(HEADER_MAGIC_V2);
-
-                // migrate headers
-                final byte[] zeroPadding = new byte[20]; // 32 (V2 work) - 12 (V1 work)
-                for (int i = currentCapacity - 1; i >= 0; i--) {
-                    byte[] record = new byte[RECORD_SIZE_V1];
-                    buffer.position(FILE_PROLOGUE_BYTES + i * RECORD_SIZE_V1);
-                    buffer.get(record);
-                    buffer.position(FILE_PROLOGUE_BYTES + i * RECORD_SIZE_V2);
-                    buffer.put(record, 0, 32); // hash
-                    buffer.put(zeroPadding);
-                    buffer.put(record, 32, RECORD_SIZE_V1 - 32); // work, height, block header
-                }
-
-                // migrate cursor
-                int cursorRecord = (getRingCursor() - FILE_PROLOGUE_BYTES) / RECORD_SIZE_V1;
-                setRingCursor(FILE_PROLOGUE_BYTES + cursorRecord * RECORD_SIZE_V2);
+                log.info("Migrating SPV block chain file from V1 to V2 format: " + file);
+                migrateV1toV2();
             }
 
             // Maybe grow.
@@ -245,6 +215,40 @@ private void initNewStore(Block genesisBlock) throws Exception {
         setChainHead(storedGenesis);
     }
 
+    private void migrateV1toV2() throws BlockStoreException, IOException {
+        long currentLength = randomAccessFile.length();
+        long currentBlocksLength = currentLength - FILE_PROLOGUE_BYTES;
+        if (currentBlocksLength % RECORD_SIZE_V1 != 0)
+            throw new BlockStoreException(
+                    "File size on disk indicates this is not a V1 block store: " + currentLength);
+        int currentCapacity = (int) (currentBlocksLength / RECORD_SIZE_V1);
+
+        randomAccessFile.setLength(fileLength);
+        // Map it into memory again because of the length change.
+        buffer.force();
+        buffer = channel.map(FileChannel.MapMode.READ_WRITE, 0, fileLength);
+
+        // migrate magic header
+        ((Buffer) buffer).rewind();
+        buffer.put(HEADER_MAGIC_V2);
+
+        // migrate headers
+        final byte[] zeroPadding = new byte[20]; // 32 (V2 work) - 12 (V1 work)
+        for (int i = currentCapacity - 1; i >= 0; i--) {
+            byte[] record = new byte[RECORD_SIZE_V1];
+            buffer.position(FILE_PROLOGUE_BYTES + i * RECORD_SIZE_V1);
+            buffer.get(record);
+            buffer.position(FILE_PROLOGUE_BYTES + i * RECORD_SIZE_V2);
+            buffer.put(record, 0, 32); // hash
+            buffer.put(zeroPadding);
+            buffer.put(record, 32, RECORD_SIZE_V1 - 32); // work, height, block header
+        }
+
+        // migrate cursor
+        int cursorRecord = (getRingCursor() - FILE_PROLOGUE_BYTES) / RECORD_SIZE_V1;
+        setRingCursor(FILE_PROLOGUE_BYTES + cursorRecord * RECORD_SIZE_V2);
+    }
+
     /** Returns the size in bytes of the file that is used to store the chain with the current parameters. */
     public static int getFileSize(int capacity) {
         return RECORD_SIZE_V2 * capacity + FILE_PROLOGUE_BYTES /* extra kilobyte for stuff */;