Yet more rework on #2925: drop (for now) support for deserializing java.sql.Blob to avoid add'l dependency

Assumption is that serialization more likely needed; also since implementation of deser bit bare-bones,
has issues; may be added if a user requests support.

Author: cowtowncoder

src/main/java/com/fasterxml/jackson/databind/ext/OptionalHandlerFactory.java

@@ -79,7 +79,8 @@ public class OptionalHandlerFactory implements java.io.Serializable
 
     public final static OptionalHandlerFactory instance = new OptionalHandlerFactory();
 
-    // classes from java.sql module, this module may not be present at runtime
+    // classes from java.sql module, this module may or may not be present at runtime
+    // (is included on Java 8, but not part of JDK core for Java 9 and beyond)
     private final Map<String, String> _sqlDeserializers;
     private final Map<String, Object> _sqlSerializers;
 
@@ -88,16 +89,15 @@ public class OptionalHandlerFactory implements java.io.Serializable
     private final static String CLS_NAME_JAVA_SQL_TIME = "java.sql.Time";
     private final static String CLS_NAME_JAVA_SQL_BLOB = "java.sql.Blob";
     private final static String CLS_NAME_JAVA_SQL_SERIALBLOB = "javax.sql.rowset.serial.SerialBlob";
-    
 
     protected OptionalHandlerFactory() {
         _sqlDeserializers = new HashMap<>();
         _sqlDeserializers.put(CLS_NAME_JAVA_SQL_DATE,
                 "com.fasterxml.jackson.databind.deser.std.DateDeserializers$SqlDateDeserializer");
         _sqlDeserializers.put(CLS_NAME_JAVA_SQL_TIMESTAMP,
                 "com.fasterxml.jackson.databind.deser.std.DateDeserializers$TimestampDeserializer");
-        _sqlDeserializers.put(CLS_NAME_JAVA_SQL_BLOB,
-                "com.fasterxml.jackson.databind.ext.SqlBlobDeserializer");
+        // 09-Nov-2020, tatu: No deserializer for `java.sql.Blob` yet; would require additional
+        //    dependency and not yet requested by anyone. Add if requested
 
         _sqlSerializers = new HashMap<>();
         // 09-Jan-2015, tatu: As per [databind#1073], let's try to guard against possibility
@@ -107,6 +107,11 @@ protected OptionalHandlerFactory() {
         _sqlSerializers.put(CLS_NAME_JAVA_SQL_TIMESTAMP, DateSerializer.instance);
         _sqlSerializers.put(CLS_NAME_JAVA_SQL_DATE, "com.fasterxml.jackson.databind.ser.std.SqlDateSerializer");
         _sqlSerializers.put(CLS_NAME_JAVA_SQL_TIME, "com.fasterxml.jackson.databind.ser.std.SqlTimeSerializer");
+
+        // 09-Nov-2020, tatu: Not really optimal way to deal with these, problem  being that
+        //   Blob is interface and actual instance we get is usually different. So may
+        //   need to improve if we reported bugs. But for now, do this
+        
         _sqlSerializers.put(CLS_NAME_JAVA_SQL_BLOB, "com.fasterxml.jackson.databind.ext.SqlBlobSerializer");
         _sqlSerializers.put(CLS_NAME_JAVA_SQL_SERIALBLOB, "com.fasterxml.jackson.databind.ext.SqlBlobSerializer");
     }

src/main/java/com/fasterxml/jackson/databind/ext/SqlBlobDeserializer.java

@@ -49,7 +49,7 @@ public static class StubA {
         private final String value;
 
         @JsonCreator(mode = JsonCreator.Mode.DELEGATING)
-        private StubA(String value) {
+        StubA(String value) {
             this.value = value;
         }
 

src/test/java/com/fasterxml/jackson/databind/ext/SqlBlobDeserializationTest.java

@@ -399,8 +399,7 @@ interface Indexed<T> {
     }
 
     public static class TestIndexed implements Indexed<String> {
-
-        private final UUID value;
+        final UUID value;
 
         @JsonCreator(mode = JsonCreator.Mode.DELEGATING)
         TestIndexed(UUID value) {
@@ -415,7 +414,7 @@ public String index() {
 
     public static final class IndexedList<T extends Indexed<K>, K> extends AbstractList<T> {
 
-        private final ArrayList<T> delegate;
+        final ArrayList<T> delegate;
 
         private IndexedList(ArrayList<T> delegate) {
             this.delegate = delegate;