fix: Derive QLDB exception, remove pointless messages

Signed-off-by: Ryan Roberts <ryan@blockchaintp.com>

src/main/java/com/blockchaintp/daml/stores/exception/StoreException.java

@@ -21,24 +21,22 @@
 public class StoreException extends IOException {
 
   /**
-   * An exception with cause and error message.
+   * An exception with an originating cause.
    *
-   * @param error
-   *          the error message
    * @param cause
-   *          the originating exception
+   *          The cause.
    */
-  protected StoreException(final String error, final Throwable cause) {
-    super(error, cause);
+  public StoreException(final Throwable cause) {
+    super(cause);
   }
 
   /**
-   * An exception with an originating cause.
+   * A de novo exception originating in our code.
    *
-   * @param cause
-   *          the cause
+   * @param message
+   *          An explanation of what happened.
    */
-  public StoreException(final Throwable cause) {
-    super(cause);
+  protected StoreException(final String message) {
+    super(message);
   }
 }

src/main/java/com/blockchaintp/daml/stores/exception/StoreReadException.java

@@ -18,18 +18,6 @@
  */
 public class StoreReadException extends StoreException {
 
-  /**
-   * Read exception with cause and error message.
-   *
-   * @param error
-   *          the error message
-   * @param cause
-   *          the originating exception
-   */
-  public StoreReadException(final String error, final Throwable cause) {
-    super(error, cause);
-  }
-
   /**
    * A read exception with an originating cause.
    *

src/main/java/com/blockchaintp/daml/stores/exception/StoreWriteException.java

@@ -17,19 +17,6 @@
  * Represents a write failure of some sort to the store.
  */
 public class StoreWriteException extends StoreException {
-
-  /**
-   * Write exception with cause and error message.
-   *
-   * @param error
-   *          the error message
-   * @param cause
-   *          the originating exception
-   */
-  public StoreWriteException(final String error, final Throwable cause) {
-    super(error, cause);
-  }
-
   /**
    * A write exception with an originating cause.
    *

src/main/java/com/blockchaintp/daml/stores/layers/Caching.java

@@ -104,7 +104,7 @@ public final Map<Key<K>, Value<V>> get(final List<Key<K>> listOfKeys) throws Sto
       return map;
 
     } catch (RuntimeException e) {
-      throw new StoreReadException("Exception while reading from store", e);
+      throw new StoreReadException(e);
     }
   }
 

src/main/java/com/blockchaintp/daml/stores/qldb/QldbStore.java

@@ -97,7 +97,7 @@ public Optional<Value<ByteString>> get(final Key<ByteString> key) throws StoreRe
       }
       return Optional.empty();
     } catch (QldbDriverException e) {
-      throw new StoreReadException("Driver error", e);
+      throw new StoreReadException(e);
     }
   }
 
@@ -142,7 +142,7 @@ public Map<Key<ByteString>, Value<ByteString>> get(final List<Key<ByteString>> l
           k -> Tuple.of(Key.of(ByteString.copyFrom(API.unchecked(() -> getIdFromRecord(k)).get().getBytes())),
               Value.of(ByteString.copyFrom(API.unchecked(() -> getHashFromRecord(k)).get().getBytes()))));
     } catch (QldbDriverException e) {
-      throw new StoreReadException("Driver", e);
+      throw new StoreReadException(e);
     }
   }
 

src/main/java/com/blockchaintp/daml/stores/qldb/QldbStoreException.java

@@ -13,28 +13,27 @@
  */
 package com.blockchaintp.daml.stores.qldb;
 
-import java.io.IOException;
-
 import com.amazon.ion.IonValue;
+import com.blockchaintp.daml.stores.exception.StoreException;
 
 /**
  * The detail of a QLDBStore exception, note this is not used to wrap S3 service issues, but purely
  * for our own faults.
  */
-public final class QldbStoreException extends IOException {
+public final class QldbStoreException extends StoreException {
   /**
    * An exception with a message.
-   * 
+   *
    * @param message
    *          Pertinent message text.
    */
-  public QldbStoreException(final String message) {
+  protected QldbStoreException(final String message) {
     super(message);
   }
 
   /**
    * We have retrieved a qldb record with an unexpected schema.
-   * 
+   *
    * @param value
    * @return The constructed exception
    */