Enhance property mechanism to support specifying multiple value types

Author: hantangwangd

presto-main-base/src/main/java/com/facebook/presto/metadata/AbstractPropertyManager.java

@@ -93,22 +93,46 @@ public final ImmutableMap.Builder<String, Object> getUserSpecifiedProperties(
                                 propertyName));
             }
 
-            Object sqlObjectValue;
+            PropertyMetadata.AdditionalSqlTypeHandler usedSqlTypeHandler = null;
+            Object sqlObjectValue = null;
             try {
                 sqlObjectValue = evaluatePropertyValue(sqlProperty.getValue(), property.getSqlType(), session, metadata, parameters);
             }
             catch (SemanticException e) {
-                throw new PrestoException(propertyError,
-                        format("Invalid value for %s property '%s': Cannot convert '%s' to %s",
-                                propertyType,
-                                property.getName(),
-                                sqlProperty.getValue(),
-                                property.getSqlType()), e);
+                for (PropertyMetadata.AdditionalSqlTypeHandler additionalSqlTypeHandler : property.getAdditionalSqlTypeHandlers()) {
+                    try {
+                        sqlObjectValue = evaluatePropertyValue(sqlProperty.getValue(), additionalSqlTypeHandler.getSqlType(), session, metadata, parameters);
+                        usedSqlTypeHandler = additionalSqlTypeHandler;
+                        break;
+                    }
+                    catch (Exception ex) {
+                        // ignored
+                    }
+                }
+
+                if (usedSqlTypeHandler == null) {
+                    String additionalTypesInfo = property.getAdditionalSqlTypeHandlers().stream()
+                            .map(handler -> handler.getSqlType().getDisplayName())
+                            .reduce((type, type2) -> type + ", " + type2)
+                            .map(message -> " or any of [" + message + "]")
+                            .orElse("");
+                    throw new PrestoException(propertyError,
+                            format("Invalid value for %s property '%s': Cannot convert '%s' to %s",
+                                    propertyType,
+                                    property.getName(),
+                                    sqlProperty.getValue(),
+                                    property.getSqlType()) + additionalTypesInfo, e);
+                }
             }
 
             Object value;
             try {
-                value = property.decode(sqlObjectValue);
+                if (usedSqlTypeHandler != null) {
+                    value = property.decode(sqlObjectValue, usedSqlTypeHandler.getDecoder());
+                }
+                else {
+                    value = property.decode(sqlObjectValue);
+                }
             }
             catch (Exception e) {
                 throw new PrestoException(propertyError,

presto-spi/src/main/java/com/facebook/presto/spi/session/PropertyMetadata.java

@@ -17,6 +17,8 @@
 import com.facebook.airlift.units.Duration;
 import com.facebook.presto.common.type.Type;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 import java.util.function.Function;
 
@@ -36,6 +38,7 @@ public final class PropertyMetadata<T>
     private final T defaultValue;
     private final Function<Object, T> decoder;
     private final Function<T, Object> encoder;
+    private final List<AdditionalSqlTypeHandler> additionalSqlTypeHandlers = new ArrayList<>();
 
     public PropertyMetadata(
             String name,
@@ -84,6 +87,11 @@ public Type getSqlType()
         return sqlType;
     }
 
+    public List<AdditionalSqlTypeHandler> getAdditionalSqlTypeHandlers()
+    {
+        return additionalSqlTypeHandlers;
+    }
+
     /**
      * Java type of this property.
      */
@@ -116,6 +124,14 @@ public T decode(Object value)
         return decoder.apply(value);
     }
 
+    /**
+     * Decodes the SQL type object value to the Java type of the property using a specified decoder.
+     */
+    public T decode(Object value, Function<Object, T> decoder)
+    {
+        return decoder.apply(value);
+    }
+
     public Function<Object, T> getDecoder()
     {
         return decoder;
@@ -134,6 +150,12 @@ public Function<T, Object> getEncoder()
         return encoder;
     }
 
+    public PropertyMetadata<?> withAdditionalTypeHandler(Type additionalSupportedType, Function<Object, T> decoder)
+    {
+        this.additionalSqlTypeHandlers.add(new AdditionalSqlTypeHandler(additionalSupportedType, decoder));
+        return this;
+    }
+
     public static PropertyMetadata<Boolean> booleanProperty(String name, String description, Boolean defaultValue, boolean hidden)
     {
         return new PropertyMetadata<>(
@@ -269,4 +291,26 @@ public int hashCode()
 
         return result;
     }
+
+    public class AdditionalSqlTypeHandler
+    {
+        Type sqlType;
+        Function<Object, T> decoder;
+
+        public AdditionalSqlTypeHandler(Type sqlType, Function<Object, T> decoder)
+        {
+            this.sqlType = sqlType;
+            this.decoder = decoder;
+        }
+
+        public Function<Object, T> getDecoder()
+        {
+            return decoder;
+        }
+
+        public Type getSqlType()
+        {
+            return sqlType;
+        }
+    }
 }