Add NetworkParameters to the Context, and verify consistency when a context is fetched.

Make Wallet accept Context as a c'tor parameter and then update unit tests (which switch params very often) to create contexts when necessary.

core/src/main/java/org/bitcoinj/core/BlockChain.java

@@ -46,7 +46,7 @@ public class BlockChain extends AbstractBlockChain {
      */
     public BlockChain(NetworkParameters params, Wallet wallet, BlockStore blockStore) throws BlockStoreException {
         this(params, new ArrayList<BlockChainListener>(), blockStore);
-        Context.getOrCreate();
+        Context.getOrCreate(params);
         if (wallet != null)
             addWallet(wallet);
     }

core/src/main/java/org/bitcoinj/core/Context.java

@@ -13,14 +13,17 @@ import static com.google.common.base.Preconditions.checkState;
  */
 public class Context {
     private static final Logger log = LoggerFactory.getLogger(Context.class);
+
     private TxConfidenceTable confidenceTable;
+    private NetworkParameters params;
 
     /**
      * Creates a new context object. For now, this will be done for you by the framework. Eventually you will be
      * expected to do this yourself in the same manner as fetching a NetworkParameters object (at the start of your app).
      */
-    public Context() {
+    public Context(NetworkParameters params) {
-        confidenceTable = new TxConfidenceTable();
+        this.confidenceTable = new TxConfidenceTable();
+        this.params = params;
         lastConstructed = this;
         // We may already have a context in our TLS slot. This can happen a lot during unit tests, so just ignore it.
         slot.set(this);
@@ -58,14 +61,18 @@ public class Context {
     }
 
     // A temporary internal shim designed to help us migrate internally in a way that doesn't wreck source compatibility.
-    static Context getOrCreate() {
+    static Context getOrCreate(NetworkParameters params) {
+        Context context;
         try {
-            return get();
+            context = get();
         } catch (IllegalStateException e) {
             log.warn("Implicitly creating context. This is a migration step and this message will eventually go away.");
-            new Context();
+            context = new Context(params);
-            return slot.get();
+            return context;
         }
+        if (context.getParams() != params)
+            throw new IllegalStateException("Context does not match implicit network params: " + context.getParams() + " vs " + params);
+        return context;
     }
 
     /**
@@ -90,4 +97,13 @@ public class Context {
     public TxConfidenceTable getConfidenceTable() {
         return confidenceTable;
     }
+
+    /**
+     * Returns the {@link org.bitcoinj.core.NetworkParameters} specified when this context was (auto) created. The
+     * network parameters defines various hard coded constants for a specific instance of a Bitcoin network, such as
+     * main net, testnet, etc.
+     */
+    public NetworkParameters getParams() {
+        return params;
+    }
 }

core/src/main/java/org/bitcoinj/core/PeerGroup.java

@@ -309,7 +309,7 @@ public class PeerGroup implements TransactionBroadcaster {
      */
     private PeerGroup(NetworkParameters params, @Nullable AbstractBlockChain chain, ClientConnectionManager connectionManager, @Nullable TorClient torClient) {
         this.params = checkNotNull(params);
-        this.context = Context.getOrCreate();
+        this.context = Context.getOrCreate(params);
         this.chain = chain;
         fastCatchupTimeSecs = params.getGenesisBlock().getTimeSeconds();
         wallets = new CopyOnWriteArrayList<Wallet>();

core/src/main/java/org/bitcoinj/core/TransactionConfidence.java

@@ -28,6 +28,8 @@ import java.util.concurrent.*;
 
 import static com.google.common.base.Preconditions.*;
 
+// TODO: Modify the getDepthInBlocks method to require the chain height to be specified, in preparation for ceasing to touch every tx on every block.
+
 /**
  * <p>A TransactionConfidence object tracks data you can use to make a confidence decision about a transaction.
  * It also contains some pre-canned rules for common scenarios: if you aren't really sure what level of confidence

core/src/main/java/org/bitcoinj/core/Wallet.java

@@ -212,6 +212,15 @@ public class Wallet extends BaseTaggableObject implements Serializable, BlockCha
         this(params, new KeyChainGroup(params));
     }
 
+    /**
+     * Creates a new, empty wallet with a randomly chosen seed and no transactions. Make sure to provide for sufficient
+     * backup! Any keys will be derived from the seed. If you want to restore a wallet from disk instead, see
+     * {@link #loadFromFile}.
+     */
+    public Wallet(Context context) {
+        this(context, new KeyChainGroup(context.getParams()));
+    }
+
     public static Wallet fromSeed(NetworkParameters params, DeterministicSeed seed) {
         return new Wallet(params, new KeyChainGroup(params, seed));
     }
@@ -244,11 +253,15 @@ public class Wallet extends BaseTaggableObject implements Serializable, BlockCha
         return new Wallet(params, group);
     }
 
+    public Wallet(NetworkParameters params, KeyChainGroup keyChainGroup) {
+        this(Context.getOrCreate(params), keyChainGroup);
+    }
+
     // TODO: When this class moves to the Wallet package, along with the protobuf serializer, then hide this.
     /** For internal use only. */
-    public Wallet(NetworkParameters params, KeyChainGroup keyChainGroup) {
+    public Wallet(Context context, KeyChainGroup keyChainGroup) {
-        this.context = Context.getOrCreate();
+        this.context = context;
-        this.params = checkNotNull(params);
+        this.params = context.getParams();
         this.keychain = checkNotNull(keyChainGroup);
         if (params == UnitTestParams.get())
             this.keychain.setLookaheadSize(5);  // Cut down excess computation for unit tests.

core/src/main/java/org/bitcoinj/testing/TestWithNetworkConnections.java

@@ -81,7 +81,7 @@ public class TestWithNetworkConnections {
         BriefLogFormatter.init();
 
         unitTestParams = UnitTestParams.get();
-        new Context();
+        new Context(unitTestParams);
         Wallet.SendRequest.DEFAULT_FEE_PER_KB = Coin.ZERO;
         this.blockStore = blockStore;
         // Allow subclasses to override the wallet object with their own.

core/src/test/java/org/bitcoinj/core/AbstractFullPrunedBlockChainTest.java

@@ -43,13 +43,13 @@ import static org.junit.Assert.*;
  * We don't do any wallet tests here, we leave that to {@link ChainSplitTest}
  */
 
-public abstract class AbstractFullPrunedBlockChainTest
+public abstract class AbstractFullPrunedBlockChainTest {
-{
     private static final Logger log = LoggerFactory.getLogger(AbstractFullPrunedBlockChainTest.class);
 
     protected NetworkParameters params;
     protected FullPrunedBlockChain chain;
     protected FullPrunedBlockStore store;
+    protected Context context;
 
     @Before
     public void setUp() throws Exception {
@@ -59,6 +59,7 @@ public abstract class AbstractFullPrunedBlockChainTest
                 return 10000;
             }
         };
+        context = new Context(params);
     }
 
     public abstract FullPrunedBlockStore createStore(NetworkParameters params, int blockCount)

core/src/test/java/org/bitcoinj/core/BlockChainTest.java

@@ -67,11 +67,13 @@ public class BlockChainTest {
     @Before
     public void setUp() throws Exception {
         BriefLogFormatter.initVerbose();
-        testNetChain = new BlockChain(testNet, new Wallet(testNet), new MemoryBlockStore(testNet));
+        Context testNetContext = new Context(testNet);
+        testNetChain = new BlockChain(testNet, new Wallet(testNetContext), new MemoryBlockStore(testNet));
         Wallet.SendRequest.DEFAULT_FEE_PER_KB = Coin.ZERO;
 
         unitTestParams = UnitTestParams.get();
-        wallet = new Wallet(unitTestParams) {
+        Context context = new Context(unitTestParams);
+        wallet = new Wallet(context) {
             @Override
             public void receiveFromBlock(Transaction tx, StoredBlock block, BlockChain.NewBlockType blockType,
                                          int relativityOffset) throws VerificationException {

core/src/test/java/org/bitcoinj/core/BloomFilterTest.java

@@ -68,6 +68,7 @@ public class BloomFilterTest {
     @Test
     public void walletTest() throws Exception {
         NetworkParameters params = MainNetParams.get();
+        Context context = new Context(params);
 
         DumpedPrivateKey privKey = new DumpedPrivateKey(params, "5Kg1gnAjaLfKiwhhPpGS3QfRg2m6awQvaj98JCZBZQ5SuS2F15C");
         
@@ -77,7 +78,7 @@ public class BloomFilterTest {
         KeyChainGroup group = new KeyChainGroup(params);
         // Add a random key which happens to have been used in a recent generation
         group.importKeys(privKey.getKey(), ECKey.fromPublicOnly(HEX.decode("03cb219f69f1b49468bd563239a86667e74a06fcba69ac50a08a5cbc42a5808e99")));
-        Wallet wallet = new Wallet(params, group);
+        Wallet wallet = new Wallet(context, group);
         wallet.commitTx(new Transaction(params, HEX.decode("01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff0d038754030114062f503253482fffffffff01c05e559500000000232103cb219f69f1b49468bd563239a86667e74a06fcba69ac50a08a5cbc42a5808e99ac00000000")));
         
         // We should have 2 per pubkey, and one for the pay-2-pubkey output we have

core/src/test/java/org/bitcoinj/core/ChainSplitTest.java

@@ -51,6 +51,7 @@ public class ChainSplitTest {
     private Address coinsTo2;
     private Address someOtherGuy;
     private MemoryBlockStore blockStore;
+    private Context context;
 
     @Before
     public void setUp() throws Exception {
@@ -58,8 +59,9 @@ public class ChainSplitTest {
         Utils.setMockClock(); // Use mock clock
         Wallet.SendRequest.DEFAULT_FEE_PER_KB = Coin.ZERO;
         unitTestParams = UnitTestParams.get();
+        context = new Context(unitTestParams);
         blockStore = new MemoryBlockStore(unitTestParams);
-        wallet = new Wallet(unitTestParams);
+        wallet = new Wallet(context);
         ECKey key1 = wallet.freshReceiveKey();
         ECKey key2 = wallet.freshReceiveKey();
         chain = new BlockChain(unitTestParams, wallet, blockStore);

core/src/test/java/org/bitcoinj/core/CoinbaseBlockTest.java

@@ -65,8 +65,8 @@ public class CoinbaseBlockTest {
         // Create a wallet contain the miner's key that receives a spend from a coinbase.
         ECKey miningKey = (new DumpedPrivateKey(params, MINING_PRIVATE_KEY)).getKey();
         assertNotNull(miningKey);
-
+        Context context = new Context(params);
-        Wallet wallet = new Wallet(params);
+        Wallet wallet = new Wallet(context);
         wallet.importKey(miningKey);
 
         // Initial balance should be zero by construction.

core/src/test/java/org/bitcoinj/core/FilteredBlockAndPartialMerkleTreeTests.java

@@ -41,6 +41,8 @@ import static org.junit.Assert.assertTrue;
 
 @RunWith(value = Parameterized.class)
 public class FilteredBlockAndPartialMerkleTreeTests extends TestWithPeerGroup {
+    private Context context;
+
     @Parameterized.Parameters
     public static Collection<ClientType[]> parameters() {
         return Arrays.asList(new ClientType[] {ClientType.NIO_CLIENT_MANAGER},
@@ -112,6 +114,7 @@ public class FilteredBlockAndPartialMerkleTreeTests extends TestWithPeerGroup {
     @Test
     public void serializeDownloadBlockWithWallet() throws Exception {
         unitTestParams = UnitTestParams.get();
+        context = new Context(unitTestParams);
         
         // First we create all the neccessary objects, including lots of serialization and double-checks
         // Note that all serialized forms here are generated by the reference client/pulled from block explorer

core/src/test/java/org/bitcoinj/core/LazyParseByteCacheTest.java

@@ -61,7 +61,8 @@ public class LazyParseByteCacheTest {
             "b6 3b 50 88 19 90 e4 b4  0d 6a ee 36 29 00 00 00" +
             "00 8b 48 30 45 02 21 00  f3 58 1e 19 72 ae 8a c7" +
             "c7 36 7a 7a 25 3b c1 13  52 23 ad b9 a4 68 bb 3a");
-    
+
+    private Context context;
     private Wallet wallet;
     private BlockStore blockStore;
     private NetworkParameters unitTestParams;
@@ -74,7 +75,7 @@ public class LazyParseByteCacheTest {
     
     private byte[] tx2Bytes;
     private byte[] tx2BytesWithHeader;
-    
+
     private void resetBlockStore() {
         blockStore = new MemoryBlockStore(unitTestParams);
     }
@@ -82,7 +83,8 @@ public class LazyParseByteCacheTest {
     @Before
     public void setUp() throws Exception {
         unitTestParams = UnitTestParams.get();
-        wallet = new Wallet(unitTestParams);
+        context = new Context(unitTestParams);
+        wallet = new Wallet(context);
         wallet.freshReceiveKey();
 
         resetBlockStore();

core/src/test/java/org/bitcoinj/core/TxConfidenceTableTest.java

@@ -35,7 +35,7 @@ public class TxConfidenceTableTest {
     @Before
     public void setup() throws Exception {
         BriefLogFormatter.init();
-        Context context = new Context();
+        Context context = new Context(params);
         table = context.getConfidenceTable();
 
         Address to = new ECKey().toAddress(params);

core/src/test/java/org/bitcoinj/wallet/DefaultRiskAnalysisTest.java

@@ -17,25 +17,19 @@
 
 package org.bitcoinj.wallet;
 
-import java.util.Arrays;
+import com.google.common.collect.*;
 import org.bitcoinj.core.*;
-import org.bitcoinj.crypto.TransactionSignature;
+import org.bitcoinj.crypto.*;
-import org.bitcoinj.params.MainNetParams;
+import org.bitcoinj.params.*;
-import org.bitcoinj.script.Script;
+import org.bitcoinj.script.*;
-import org.bitcoinj.script.ScriptBuilder;
+import org.bitcoinj.wallet.DefaultRiskAnalysis.*;
-import org.bitcoinj.script.ScriptChunk;
+import org.junit.*;
-import com.google.common.collect.ImmutableList;
-import org.bitcoinj.wallet.DefaultRiskAnalysis;
-import org.bitcoinj.wallet.RiskAnalysis;
-import org.bitcoinj.wallet.DefaultRiskAnalysis.RuleViolation;
-import org.junit.Before;
-import org.junit.Test;
 
-import static org.bitcoinj.core.Coin.COIN;
+import java.util.*;
-import static org.bitcoinj.script.ScriptOpCodes.OP_PUSHDATA1;
+
-import static org.junit.Assert.assertEquals;
+import static org.bitcoinj.core.Coin.*;
-import static org.junit.Assert.assertNull;
+import static org.bitcoinj.script.ScriptOpCodes.*;
-import static org.junit.Assert.fail;
+import static org.junit.Assert.*;
 
 public class DefaultRiskAnalysisTest {
     // Uses mainnet because isStandard checks are disabled on testnet.
@@ -47,7 +41,7 @@ public class DefaultRiskAnalysisTest {
 
     @Before
     public void setup() {
-        wallet = new Wallet(params) {
+        wallet = new Wallet(new Context(params)) {
             @Override
             public int getLastBlockSeenHeight() {
                 return 1000;