#73 Fix issues brought up in pull request

Author: martti007

src/main/java/org/unicitylabs/sdk/api/NetworkId.java

@@ -23,18 +23,17 @@ private NetworkId(short id) {
   }
 
   /**
-   * Resolve a NetworkId from its numeric identifier. Returns the registered
-   * singleton for known ids; constructs a new (unnamed) instance for any
-   * other 16-bit value.
+   * Resolve a NetworkId from its raw 16-bit identifier. Returns the registered singleton for
+   * known ids; constructs a new (unnamed) instance for any other value.
    *
-   * @param id numeric network identifier
+   * @param id raw 16-bit network identifier
    * @return NetworkId for the given identifier
    */
   public static NetworkId fromId(short id) {
-    if (id <= 0) {
-      throw new IllegalArgumentException(
-          "Network identifier out of allowed 16-bit unsigned range: " + id + ".");
+    if (id == 0) {
+      throw new IllegalArgumentException("Network identifier cannot be zero.");
     }
+
     if (id == MAINNET.id) {
       return MAINNET;
     }

src/main/java/org/unicitylabs/sdk/api/bft/RootTrustBase.java

@@ -54,9 +54,12 @@ public class RootTrustBase {
               String.format("Unsupported RootTrustBase version: %s", version));
     }
 
+    Objects.requireNonNull(rootNodes, "rootNodes cannot be null");
+
     Map<String, NodeInfo> nodes = new LinkedHashMap<>();
     Set<String> signingKeys = new HashSet<>();
     for (NodeInfo node : rootNodes) {
+      Objects.requireNonNull(node, "Trust base node cannot be null");
       if (nodes.putIfAbsent(node.getNodeId(), node) != null) {
         throw new IllegalArgumentException(
                 String.format("Duplicate trust base node id: %s", node.getNodeId()));
@@ -250,6 +253,8 @@ public static class NodeInfo {
             @JsonProperty("sigKey") byte[] signingKey,
             @JsonProperty("stake") long stakedAmount
     ) {
+      Objects.requireNonNull(nodeId, "Node id cannot be null");
+      Objects.requireNonNull(signingKey, "Node signing key cannot be null");
       if (stakedAmount <= 0) {
         throw new IllegalArgumentException("Each trust base root node must have positive stake.");
       }

src/main/java/org/unicitylabs/sdk/api/jsonrpc/JsonRpcHttpTransport.java

@@ -10,6 +10,7 @@
 import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 
@@ -23,6 +24,11 @@ public class JsonRpcHttpTransport {
 
   private static final MediaType MEDIA_TYPE_JSON = MediaType.get("application/json; charset=utf-8");
 
+  private static final OkHttpClient DEFAULT_HTTP_CLIENT = new OkHttpClient.Builder()
+          .followRedirects(false)
+          .followSslRedirects(false)
+          .build();
+
   private final String url;
   private final int maxResponseBytes;
   private final OkHttpClient httpClient;
@@ -43,12 +49,32 @@ public JsonRpcHttpTransport(String url) {
    * @param maxResponseBytes maximum response body size in bytes
    */
   public JsonRpcHttpTransport(String url, int maxResponseBytes) {
-    this.url = url;
+    this(url, JsonRpcHttpTransport.DEFAULT_HTTP_CLIENT, maxResponseBytes);
+  }
+
+  /**
+   * JSON-RPC HTTP service constructor with a caller-supplied HTTP client, to share a single
+   * connection and thread pool across transports.
+   *
+   * @param url service URL
+   * @param httpClient OkHttp client to use
+   */
+  public JsonRpcHttpTransport(String url, OkHttpClient httpClient) {
+    this(url, httpClient, JsonRpcHttpTransport.DEFAULT_MAX_RESPONSE_BYTES);
+  }
+
+  /**
+   * JSON-RPC HTTP service constructor with a caller-supplied HTTP client, to share a single
+   * connection and thread pool across transports.
+   *
+   * @param url service URL
+   * @param httpClient OkHttp client to use
+   * @param maxResponseBytes maximum response body size in bytes
+   */
+  public JsonRpcHttpTransport(String url, OkHttpClient httpClient, int maxResponseBytes) {
+    this.url = Objects.requireNonNull(url, "url cannot be null");
+    this.httpClient = Objects.requireNonNull(httpClient, "httpClient cannot be null");
     this.maxResponseBytes = maxResponseBytes;
-    this.httpClient = new OkHttpClient.Builder()
-            .followRedirects(false)
-            .followSslRedirects(false)
-            .build();
   }
 
   /**
@@ -80,6 +106,10 @@ public <T> CompletableFuture<T> request(
           Class<T> resultType,
           Map<String, List<String>> headers
   ) {
+    Objects.requireNonNull(method, "method cannot be null");
+    Objects.requireNonNull(resultType, "resultType cannot be null");
+    Objects.requireNonNull(headers, "headers cannot be null");
+
     CompletableFuture<T> future = new CompletableFuture<>();
 
     try {

src/main/java/org/unicitylabs/sdk/payment/SplitAllocationProof.java

@@ -19,6 +19,7 @@
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 
 /**
  * Split allocation inclusion proof for one output asset: the explicit-depth inclusion proof of a
@@ -58,6 +59,12 @@ public int getLength() {
    * @throws IllegalArgumentException if the key is not present in the tree
    */
   public static SplitAllocationProof create(SparseMerkleSumTreeRootNode root, byte[] key) {
+    Objects.requireNonNull(root, "root cannot be null");
+    Objects.requireNonNull(key, "key cannot be null");
+    if (key.length != 32) {
+      throw new IllegalArgumentException("Key must be 32 bytes long.");
+    }
+
     BigInteger keyPath = BitString.fromBytesReversedLSB(key).toBigInteger();
     List<Sibling> siblings = new ArrayList<>();
 
@@ -111,7 +118,7 @@ public static SplitAllocationProof fromCbor(byte[] bytes) {
     for (byte[] entry : entries) {
       List<byte[]> fields = CborDeserializer.decodeArray(entry, 3);
 
-      int depth = CborDeserializer.decodeUnsignedInteger(fields.get(0)).asInt();
+      int depth = CborDeserializer.decodeUnsignedInteger(fields.get(0)).asListSize();
       if (depth > SplitAllocationProof.MAX_DEPTH) {
         throw new CborSerializationException("Sibling depth must be in the range [0, 255].");
       }

src/main/java/org/unicitylabs/sdk/payment/SplitMintJustification.java

@@ -75,6 +75,11 @@ public static byte[] calculateLeafData(
           TokenId tokenId,
           byte[] data
   ) {
+    Objects.requireNonNull(token, "token cannot be null");
+    Objects.requireNonNull(recipient, "recipient cannot be null");
+    Objects.requireNonNull(salt, "salt cannot be null");
+    Objects.requireNonNull(tokenId, "tokenId cannot be null");
+
     return new DataHasher(HashAlgorithm.SHA256)
             .update(
                     CborSerializer.encodeArray(

src/main/java/org/unicitylabs/sdk/serializer/cbor/CborDeserializer.java

@@ -45,9 +45,9 @@ public static <T> T decodeNullable(byte[] data, Function<byte[], T> decoder) {
    * @param data bytes
    * @return unsigned number
    */
-  public static CborNumber decodeUnsignedInteger(byte[] data) {
+  public static CborUnsignedLong decodeUnsignedInteger(byte[] data) {
     CborReader reader = new CborReader(data);
-    CborNumber value = reader.readLength(CborMajorType.UNSIGNED_INTEGER);
+    CborUnsignedLong value = reader.readLength(CborMajorType.UNSIGNED_INTEGER);
     reader.assertExhausted();
 
     return value;
@@ -61,7 +61,7 @@ public static CborNumber decodeUnsignedInteger(byte[] data) {
    */
   public static byte[] decodeByteString(byte[] data) {
     CborReader reader = new CborReader(data);
-    byte[] result = reader.read(reader.readLength(CborMajorType.BYTE_STRING).asInt());
+    byte[] result = reader.read(reader.readLength(CborMajorType.BYTE_STRING).asListSize());
     reader.assertExhausted();
 
     return result;
@@ -108,7 +108,7 @@ public static BigInteger decodeBigInteger(byte[] data, Integer maxByteLength) {
    */
   public static String decodeTextString(byte[] data) {
     CborReader reader = new CborReader(data);
-    byte[] bytes = reader.read(reader.readLength(CborMajorType.TEXT_STRING).asInt());
+    byte[] bytes = reader.read(reader.readLength(CborMajorType.TEXT_STRING).asListSize());
     reader.assertExhausted();
 
     return new String(bytes);
@@ -122,7 +122,7 @@ public static String decodeTextString(byte[] data) {
    */
   public static List<byte[]> decodeArray(byte[] data) {
     CborReader reader = new CborReader(data);
-    int length = reader.readLength(CborMajorType.ARRAY).asInt();
+    int length = reader.readLength(CborMajorType.ARRAY).asListSize();
 
     ArrayList<byte[]> result = new ArrayList<>();
     for (int i = 0; i < length; i++) {
@@ -160,7 +160,7 @@ public static List<byte[]> decodeArray(byte[] data, long expectedLength) {
    */
   public static Set<CborMap.Entry> decodeMap(byte[] data) {
     CborReader reader = new CborReader(data);
-    int length = reader.readLength(CborMajorType.MAP).asInt();
+    int length = reader.readLength(CborMajorType.MAP).asListSize();
 
     Set<Entry> result = new LinkedHashSet<>();
     Entry previous = null;
@@ -258,7 +258,7 @@ public byte[] read(int length) {
       }
     }
 
-    public CborNumber readLength(CborMajorType majorType) {
+    public CborUnsignedLong readLength(CborMajorType majorType) {
       byte initialByte = this.readByte();
 
       CborMajorType parsedMajorType = CborMajorType.fromType(
@@ -271,7 +271,7 @@ public CborNumber readLength(CborMajorType majorType) {
       byte additionalInformation = (byte) (initialByte
               & CborDeserializer.ADDITIONAL_INFORMATION_MASK);
       if (Byte.compareUnsigned(additionalInformation, (byte) 24) < 0) {
-        return new CborNumber(additionalInformation);
+        return new CborUnsignedLong(additionalInformation);
       }
 
       switch (majorType) {
@@ -307,7 +307,7 @@ public CborNumber readLength(CborMajorType majorType) {
                 length, Long.toUnsignedString(t)));
       }
 
-      return new CborNumber(t);
+      return new CborUnsignedLong(t);
     }
 
     public byte[] readRawCbor() {
@@ -323,19 +323,19 @@ public byte[] readRawCbor() {
 
         CborMajorType majorType = CborMajorType.fromType(
                 this.data[this.position] & CborDeserializer.MAJOR_TYPE_MASK);
-        CborNumber length = this.readLength(majorType);
+        CborUnsignedLong length = this.readLength(majorType);
         switch (majorType) {
           case BYTE_STRING:
           case TEXT_STRING:
-            this.read(length.asInt());
+            this.read(length.asListSize());
             break;
           case ARRAY:
             // asInt bounds each count and every header consumes input, so the counter cannot
             // overflow; undersupplied counts fail with premature end of data as items are read.
-            remaining += length.asInt();
+            remaining += length.asListSize();
             break;
           case MAP:
-            remaining += length.asInt() * 2L;
+            remaining += length.asListSize() * 2L;
             break;
           case TAG:
             remaining += 1;
@@ -384,59 +384,82 @@ public byte[] getData() {
   /**
    * CBOR number implementation.
    */
-  public static class CborNumber {
+  public static class CborUnsignedLong {
 
     private final long value;
 
-    private CborNumber(long value) {
+    private CborUnsignedLong(long value) {
       this.value = value;
     }
 
     /**
-     * Get number as long.
+     * Get the raw unsigned value as a {@code long}. Values at or above {@code 2^63} are returned
+     * as a negative long with the same bit pattern; use {@link Long#compareUnsigned} to compare
+     * them.
      *
-     * @return number
+     * @return value
      */
     public long asLong() {
       return this.value;
     }
 
     /**
-     * Get number as int, throw error if does not fit.
+     * Get the value as an unsigned 32-bit integer, throwing if it exceeds {@code 0xFFFFFFFF}.
+     * Values above {@link Integer#MAX_VALUE} are returned with the same bit pattern (a negative
+     * {@code int}); mask with {@code & 0xFFFFFFFFL} to recover the unsigned value.
      *
-     * @return number
+     * @return value
      */
     public int asInt() {
-      if (Long.compareUnsigned(this.value, Integer.MAX_VALUE) > 0) {
+      if (Long.compareUnsigned(this.value, 0xFFFFFFFFL) > 0) {
         throw new CborSerializationException("Value too large");
       }
       return (int) this.value;
     }
 
     /**
-     * Get number as byte, throw error if does not fit.
+     * Get the value as an unsigned 16-bit integer, throwing if it exceeds {@code 0xFFFF}. Values
+     * above {@link Short#MAX_VALUE} are returned with the same bit pattern (a negative
+     * {@code short}); mask with {@code & 0xFFFF} to recover the unsigned value.
      *
-     * @return number
+     * @return value
+     */
+    public short asShort() {
+      if (Long.compareUnsigned(this.value, 0xFFFFL) > 0) {
+        throw new CborSerializationException("Value too large");
+      }
+
+      return (short) this.value;
+    }
+
+    /**
+     * Get the value as an unsigned 8-bit integer, throwing if it exceeds {@code 0xFF}. Values
+     * above {@link Byte#MAX_VALUE} are returned with the same bit pattern (a negative
+     * {@code byte}); mask with {@code & 0xFF} to recover the unsigned value.
+     *
+     * @return value
      */
     public byte asByte() {
-      if (Long.compareUnsigned(this.value, Byte.MAX_VALUE) > 0) {
+      if (Long.compareUnsigned(this.value, 0xFFL) > 0) {
         throw new CborSerializationException("Value too large");
       }
 
       return (byte) this.value;
     }
 
     /**
-     * Get number as short, throw error if does not fit.
+     * Get the value as a non-negative {@code int} bounded to {@link Integer#MAX_VALUE}, suitable
+     * for a collection size, byte-string length or index. Throws if the value would not fit in a
+     * valid Java array size.
      *
-     * @return number
+     * @return value
      */
-    public short asShort() {
-      if (Long.compareUnsigned(this.value, Short.MAX_VALUE) > 0) {
+    public int asListSize() {
+      if (Long.compareUnsigned(this.value, Integer.MAX_VALUE) > 0) {
         throw new CborSerializationException("Value too large");
       }
 
-      return (short) this.value;
+      return (int) this.value;
     }
   }
 }

src/main/java/org/unicitylabs/sdk/transaction/verification/TokenIssuanceVerifierService.java

@@ -8,6 +8,7 @@
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Objects;
 
 /**
  * Registry that dispatches token verification to the right {@link TokenIssuanceVerifier} based on
@@ -46,6 +47,7 @@ public TokenIssuanceVerifierService(boolean rejectUnregisteredTypes) {
    * @throws IllegalArgumentException if a policy is already registered for the token type
    */
   public TokenIssuanceVerifierService register(TokenIssuanceVerifier verifier) {
+    Objects.requireNonNull(verifier, "verifier cannot be null");
     String key = HexConverter.encode(verifier.getTokenType().getBytes());
     if (this.verifiers.containsKey(key)) {
       throw new IllegalArgumentException(String.format(