Payment channels: add wallet printouts of the contents of the extensions.

core/src/main/java/com/google/bitcoin/protocols/channels/StoredPaymentChannelClientStates.java

@@ -201,6 +201,19 @@ public class StoredPaymentChannelClientStates implements WalletExtension {
             lock.unlock();
         }
     }
+
+    @Override
+    public String toString() {
+        lock.lock();
+        try {
+            StringBuilder buf = new StringBuilder("Client payment channel states:\n");
+            for (StoredClientChannel channel : mapChannels.values())
+                buf.append("  ").append(channel).append("\n");
+            return buf.toString();
+        } finally {
+            lock.unlock();
+        }
+    }
 }
 
 /**
@@ -227,4 +240,18 @@ class StoredClientChannel {
         this.refundFees = refundFees;
         this.active = active;
     }
+
+    @Override
+    public String toString() {
+        final String newline = String.format("%n");
+        return String.format("Stored client channel %s (%s)%n" +
+                             "    Key:         %s%n" +
+                             "    Value to me: %d%n" +
+                             "    Refund fees: %d%n" +
+                             "    Contract:  %s" +
+                             "Refund:    %s",
+                id, active ? "active" : "inactive", myKey, valueToMe, refundFees,
+                contract.toString().replaceAll(newline, newline + "    "),
+                refund.toString().replaceAll(newline, newline + "    "));
+    }
 }

core/src/main/java/com/google/bitcoin/protocols/channels/StoredPaymentChannelServerStates.java

@@ -185,4 +185,18 @@ public class StoredPaymentChannelServerStates implements WalletExtension {
             lock.unlock();
         }
     }
+
+    @Override
+    public String toString() {
+        lock.lock();
+        try {
+            StringBuilder buf = new StringBuilder();
+            for (StoredServerChannel stored : mapChannels.values()) {
+                buf.append(stored);
+            }
+            return buf.toString();
+        } finally {
+            lock.unlock();
+        }
+    }
 }

core/src/main/java/com/google/bitcoin/protocols/channels/StoredServerChannel.java

@@ -19,6 +19,7 @@ package com.google.bitcoin.protocols.channels;
 import com.google.bitcoin.core.*;
 
 import java.math.BigInteger;
+import java.util.Date;
 
 import static com.google.common.base.Preconditions.checkArgument;
 
@@ -85,4 +86,18 @@ public class StoredServerChannel {
         checkArgument(wallet == state.wallet);
         return state;
     }
+
+    @Override
+    public synchronized String toString() {
+        final String newline = String.format("%n");
+        return String.format("Stored server channel (%s)%n" +
+                "    Key:           %s%n" +
+                "    Value to me:   %d%n" +
+                "    Client output: %s%n" +
+                "    Refund unlock: %s (%d unix time)%n" +
+                "    Contract:    %s%n",
+                connectedHandler != null ? "connected" : "disconnected", myKey, bestValueToMe,
+                clientOutput,  new Date(refundTransactionUnlockTimeSecs * 1000), refundTransactionUnlockTimeSecs,
+                contract.toString().replaceAll(newline, newline + "    "));
+    }
 }