Merge pull request #2028 from ClickHouse/add-enum-string-v2

Enum Code + Test

Author: Paultagoras

client-v2/src/main/java/com/clickhouse/client/api/data_formats/internal/AbstractBinaryFormatReader.java

@@ -10,6 +10,8 @@
 import com.clickhouse.client.api.query.POJOSetter;
 import com.clickhouse.client.api.query.QuerySettings;
 import com.clickhouse.data.ClickHouseColumn;
+import com.clickhouse.data.ClickHouseDataType;
+import com.clickhouse.data.ClickHouseEnum;
 import com.clickhouse.data.value.ClickHouseBitmap;
 import com.clickhouse.data.value.ClickHouseGeoMultiPolygonValue;
 import com.clickhouse.data.value.ClickHouseGeoPointValue;
@@ -251,6 +253,8 @@ protected void setSchema(TableSchema schema) {
                 case Decimal256:
                 case Bool:
                 case String:
+                case Enum8:
+                case Enum16:
                     this.convertions[i] = NumberConverter.NUMBER_CONVERTERS;
                     break;
                 default:
@@ -275,20 +279,19 @@ public String getString(String colName) {
             return null;
         } else if (value instanceof String) {
             return (String) value;
+        } else {
+            ClickHouseDataType dataType = schema.getColumnByName(colName).getDataType();
+            if (dataType == ClickHouseDataType.Enum8 || dataType == ClickHouseDataType.Enum16) {
+                ClickHouseEnum clickHouseEnum = schema.getColumnByName(colName).getEnumConstants();
+                return clickHouseEnum.name(Integer.parseInt(value.toString()));
+            }
         }
         return value.toString();
     }
 
     @Override
     public String getString(int index) {
-        // TODO: it may be incorrect to call .toString() on some objects
-        Object value = readValue(index);
-        if (value == null) {
-            return null;
-        } else if (value instanceof String) {
-            return (String) value;
-        }
-        return value.toString();
+        return getString(schema.columnIndexToName(index));
     }
 
     private <T> T readNumberValue(String colName, NumberConverter.NumberType targetType) {

client-v2/src/test/java/com/clickhouse/client/query/QueryTests.java

@@ -1958,6 +1958,31 @@ public void testReadingSimpleAggregateFunction() throws Exception {
         }
     }
 
+    @Test(groups = {"integration"})
+    public void testReadingEnumsAsStrings() throws Exception {
+        final String tableName = "enums_as_strings_test_table";
+        client.execute("DROP TABLE IF EXISTS " + tableName).get();
+        client.execute("CREATE TABLE `" + tableName + "` " +
+                "(idx UInt8, enum1 Enum8('a' = 1, 'b' = 2, 'c' = 3), enum2 Enum16('atch' = 1, 'batch' = 2, 'catch' = 3)) " +
+                "ENGINE Memory").get();
+
+        try (InsertResponse response = client.insert(tableName, new ByteArrayInputStream("1\ta\t2".getBytes(StandardCharsets.UTF_8)), ClickHouseFormat.TSV).get(30, TimeUnit.SECONDS)) {
+            Assert.assertEquals(response.getWrittenRows(), 1);
+        }
+
+        try (QueryResponse queryResponse = client.query("SELECT * FROM " + tableName + " LIMIT 1").get(30, TimeUnit.SECONDS)) {
+            ClickHouseBinaryFormatReader reader = client.newBinaryFormatReader(queryResponse);
+            Assert.assertNotNull(reader.next());
+            Assert.assertEquals(reader.getByte("idx"), Byte.valueOf("1"));
+            Assert.assertEquals(reader.getString("enum1"), "a");
+            Assert.assertEquals(reader.getShort("enum1"), 1);
+            Assert.assertEquals(reader.getInteger("enum1"), 1);
+            Assert.assertEquals(reader.getString("enum2"), "batch");
+            Assert.assertEquals(reader.getShort("enum2"), 2);
+            Assert.assertEquals(reader.getInteger("enum2"), 2);
+            Assert.assertFalse(reader.hasNext());
+        }
+    }
 
     @Test(groups = {"integration"})
     public void testServerTimezone() throws Exception {

jdbc-v2/src/main/java/com/clickhouse/jdbc/PreparedStatementImpl.java

@@ -457,6 +457,8 @@ public long executeLargeUpdate() throws SQLException {
     }
 
     private static String encodeObject(Object x) throws SQLException {
+        LOG.trace("Encoding object: {}", x);
+
         try {
             if (x == null) {
                 return "NULL";
@@ -500,14 +502,14 @@ private static String encodeObject(Object x) throws SQLException {
                 listString.append("]");
 
                 return listString.toString();
-            } else if (x instanceof Map) {
-                Map<?, ?> tmpMap = (Map<?, ?>) x;
+            } else if (x instanceof Map<?, ?> tmpMap) {
                 StringBuilder mapString = new StringBuilder();
                 mapString.append("{");
                 for (Object key : tmpMap.keySet()) {
                     mapString.append(encodeObject(key)).append(": ").append(encodeObject(tmpMap.get(key))).append(", ");
                 }
-                mapString.delete(mapString.length() - 2, mapString.length());
+                if (!tmpMap.isEmpty())
+                    mapString.delete(mapString.length() - 2, mapString.length());
                 mapString.append("}");
 
                 return mapString.toString();

jdbc-v2/src/test/java/com/clickhouse/jdbc/DataTypeTests.java

@@ -354,9 +354,12 @@ public void testStringTypes() throws SQLException {
                     assertTrue(rs.next());
                     assertEquals(rs.getString("str"), str);
                     assertEquals(rs.getString("fixed"), fixed);
-                    assertEquals(rs.getString("enum"), "6");
-                    assertEquals(rs.getString("enum8"), "1");
-                    assertEquals(rs.getString("enum16"), "2");
+                    assertEquals(rs.getString("enum"), "a");
+                    assertEquals(rs.getInt("enum"), 6);
+                    assertEquals(rs.getString("enum8"), "a");
+                    assertEquals(rs.getInt("enum8"), 1);
+                    assertEquals(rs.getString("enum16"), "b");
+                    assertEquals(rs.getInt("enum16"), 2);
                     assertEquals(rs.getString("uuid"), uuid);
                     assertEquals(rs.getString("ipv4"), "/" + ipv4);
                     assertEquals(rs.getString("ipv6"), "/" + ipv6);