From a1703725626bd8c461ddba42a97ccd81e4a8cbfc Mon Sep 17 00:00:00 2001
From: Mike Hearn <hearn@google.com>
Date: Fri, 6 Apr 2012 14:58:36 +0200
Subject: [PATCH] Add a static method to go from string ID to NetworkParameters
 and use it to simplify the WalletProtobufSerializer API.

---
 .../bitcoin/core/NetworkParameters.java       | 11 ++++++++
 .../store/WalletProtobufSerializer.java       | 25 +++++++------------
 .../store/WalletProtobufSerializerTest.java   |  2 +-
 3 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/core/src/main/java/com/google/bitcoin/core/NetworkParameters.java b/core/src/main/java/com/google/bitcoin/core/NetworkParameters.java
index 85c389e80..c0119672b 100644
--- a/core/src/main/java/com/google/bitcoin/core/NetworkParameters.java
+++ b/core/src/main/java/com/google/bitcoin/core/NetworkParameters.java
@@ -215,4 +215,15 @@ public class NetworkParameters implements Serializable {
         }
         return id;
     }
+
+    /** Returns the network parameters for the given string ID or NULL if not recognized. */
+    public static NetworkParameters fromID(String id) {
+        if (id.equals(ID_PRODNET)) {
+            return prodNet();
+        } else if (id.equals(ID_TESTNET)) {
+            return testNet();
+        } else {
+            return null;
+        }
+    }
 }
diff --git a/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java b/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
index 96c7f8752..41800fa22 100644
--- a/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
+++ b/core/src/main/java/com/google/bitcoin/store/WalletProtobufSerializer.java
@@ -36,7 +36,7 @@ import java.util.Map;
  * Serialize and de-serialize a wallet to a byte stream containing a
  * <a href="http://code.google.com/apis/protocolbuffers/docs/overview.html">protocol buffer</a>. Protocol buffers are
  * a data interchange format developed by Google with an efficient binary representation, a type safe specification
- * languaeg and compilers that generate code to work with those data structures for many languages. Protocol buffers
+ * language and compilers that generate code to work with those data structures for many languages. Protocol buffers
  * can have their format evolved over time: conceptually they represent data using (tag, length, value) tuples. The
  * format is defined by the <tt>bitcoin.proto</tt> file in the BitCoinJ source distribution.<p>
  *
@@ -73,9 +73,10 @@ public class WalletProtobufSerializer {
 
     /**
      * Returns the given wallet formatted as text. The text format is that used by protocol buffers and although it
-     * can also be parsed using {@link TextFormat.merge()}, it is designed more for debugging than storage. It is not 
-     * well specified and wallets are largely binary data structures anyway, consisting as they do of keys (large
-     * random numbers) and {@link Transaction}s which also mostly contain keys and hashes.
+     * can also be parsed using {@link TextFormat#merge(CharSequence, com.google.protobuf.Message.Builder)},
+     * it is designed more for debugging than storage. It is not well specified and wallets are largely binary data
+     * structures anyway, consisting as they do of keys (large random numbers) and {@link Transaction}s which also
+     * mostly contain keys and hashes.
      */
     public static String walletToText(Wallet wallet) {
         Protos.Wallet walletProto = walletToProto(wallet);
@@ -199,26 +200,18 @@ public class WalletProtobufSerializer {
 
     /**
      * Parses a wallet from the given stream. The stream is expected to contain a binary serialization of a 
-     * {@link Protos.Wallet} object. You must also specify the {@link NetworkParameters} the wallet will use,
-     * it will be checked against the stream to ensure the right params have been specified. In future this
-     * parameter will probably go away.<p>
+     * {@link Protos.Wallet} object.<p>
      *     
      * If the stream is invalid or the serialized wallet contains unsupported features, 
      * {@link IllegalArgumentException} is thrown.
      *
-     * @param input
-     * @param params
-     * @return
-     * @throws IOException
      */
-    public static Wallet readWallet(InputStream input, NetworkParameters params) throws IOException {
+    public static Wallet readWallet(InputStream input) throws IOException {
         // TODO: This method should throw more specific exception types than IllegalArgumentException.
         WalletProtobufSerializer serializer = new WalletProtobufSerializer();
         Protos.Wallet walletProto = Protos.Wallet.parseFrom(input);
-        if (!params.getId().equals(walletProto.getNetworkIdentifier()))
-            throw new IllegalArgumentException("Trying to read a wallet with a different network id " +
-                                                walletProto.getNetworkIdentifier());
-        
+
+        NetworkParameters params = NetworkParameters.fromID(walletProto.getNetworkIdentifier());
         Wallet wallet = new Wallet(params);
         
         // Read all keys
diff --git a/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java b/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
index 58403cfe0..8e0225cac 100644
--- a/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
+++ b/core/src/test/java/com/google/bitcoin/store/WalletProtobufSerializerTest.java
@@ -110,6 +110,6 @@ public class WalletProtobufSerializerTest {
         //System.out.println(WalletProtobufSerializer.walletToText(wallet));
         WalletProtobufSerializer.writeWallet(wallet, output);
         ByteArrayInputStream input = new ByteArrayInputStream(output.toByteArray());
-        return WalletProtobufSerializer.readWallet(input, params);
+        return WalletProtobufSerializer.readWallet(input);
     }
 }