Initial Data Model for Schema SQL Generation

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/schemasqlgeneration/BaseTypeMapper.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.relational.core.mapping.schemasqlgeneration;
+
+import java.util.HashMap;
+
+public class BaseTypeMapper {
+
+    final HashMap<Class<?>,String> mapClassToDatabaseType = new HashMap<Class<?>,String>();
+
+    public BaseTypeMapper() {
+        mapClassToDatabaseType.put(String.class, "VARCHAR(255)");
+        mapClassToDatabaseType.put(Boolean.class, "TINYINT");
+        mapClassToDatabaseType.put(Double.class, "DOUBLE");
+        mapClassToDatabaseType.put(Float.class, "FLOAT");
+        mapClassToDatabaseType.put(Integer.class, "INT");
+    }
+    public String databaseTypeFromClass(Class<?> type) {
+        return mapClassToDatabaseType.get(type);
+    }
+}

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/schemasqlgeneration/ColumnModel.java

@@ -29,16 +29,16 @@ public class ColumnModel implements Serializable {
     @Serial
     private static final long serialVersionUID = 1L;
     private final SqlIdentifier name;
-    private final Class<?> type;
+    private final String type;
     private final boolean nullable;
 
-    public ColumnModel(SqlIdentifier name, Class<?> type, boolean nullable) {
+    public ColumnModel(SqlIdentifier name, String type, boolean nullable) {
         this.name = name;
         this.type = type;
         this.nullable = nullable;
     }
 
-    public ColumnModel(SqlIdentifier name, Class<?> type) {
+    public ColumnModel(SqlIdentifier name, String type) {
         this.name = name;
         this.type = type;
         this.nullable = false;
@@ -48,7 +48,7 @@ public SqlIdentifier getName() {
         return name;
     }
 
-    public Class<?> getType() {
+    public String getType() {
         return type;
     }
 

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/schemasqlgeneration/SchemaSQLGenerationDataModel.java

@@ -23,6 +23,7 @@
 import java.io.Serial;
 import java.io.Serializable;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 
@@ -36,6 +37,7 @@ public class SchemaSQLGenerationDataModel implements Serializable {
     @Serial
     private static final long serialVersionUID = 1L;
     private final List<TableModel> tableData = new ArrayList<TableModel>();
+    BaseTypeMapper typeMapper;
 
     /**
      * Default constructor so that we can deserialize a model
@@ -48,6 +50,10 @@ public SchemaSQLGenerationDataModel() {
      */
     public SchemaSQLGenerationDataModel(RelationalMappingContext context) {
 
+        if (typeMapper == null) {
+            typeMapper = new BaseTypeMapper();
+        }
+
         for (RelationalPersistentEntity entity : context.getPersistentEntities()) {
             TableModel tableModel = new TableModel(entity.getTableName());
 
@@ -56,7 +62,9 @@ public SchemaSQLGenerationDataModel(RelationalMappingContext context) {
 
             while (iter.hasNext()) {
                 BasicRelationalPersistentProperty p = iter.next();
-                ColumnModel columnModel = new ColumnModel(p.getColumnName(), p.getActualType());
+                ColumnModel columnModel = new ColumnModel(p.getColumnName(),
+                        typeMapper.databaseTypeFromClass(p.getActualType()),
+                        true);
                 tableModel.getColumns().add(columnModel);
             }
             tableData.add(tableModel);