Initial commit of the Schema class

Author: pborissow

src/javaxt/orm/Schema.java

@@ -0,0 +1,114 @@
+package javaxt.orm;
+
+//******************************************************************************
+//**  Schema Class
+//******************************************************************************
+/**
+ *   Used to generate an SQL schema for a given set of Models
+ *
+ ******************************************************************************/
+
+public class Schema {
+
+    private Model[] models;
+
+
+  //**************************************************************************
+  //** Constructor
+  //**************************************************************************
+    public Schema(Model[] models){
+        this.models = models;
+    }
+
+
+  //**************************************************************************
+  //** getSQL
+  //**************************************************************************
+  /** Returns a SQL script used to generate tables and indexes in a relational
+   *  database.
+   */
+    public String getSQLScript(){
+        boolean hasGeometry = false;
+        boolean hasLastModifiedField = false;
+        java.util.HashSet<String> schemas = new java.util.HashSet<String>();
+        for (Model model : models){
+
+
+          //Check whether any of the fields are geospatial/geometry types
+            if (!hasGeometry){
+                for (Field field : model.getFields()){
+                    if (field.getColumnType().startsWith("geometry")){
+                        hasGeometry = true;
+                        break;
+                    }
+                }
+            }
+
+            if (model.hasLastModifiedField()){
+                hasLastModifiedField = true;
+            }
+
+
+            String schemaName = model.getSchemaName();
+            if (schemaName!=null){
+                schemas.add(model.escapeTableName(schemaName));
+            }
+        }
+
+
+      //Generate SQL script
+        StringBuilder sql = new StringBuilder();
+
+        for (String schemaName : schemas){
+            sql.append("CREATE SCHEMA IF NOT EXISTS ");
+            sql.append(schemaName);
+            sql.append(";\r\n");
+        }
+
+        if (hasGeometry){
+            sql.append("CREATE EXTENSION IF NOT EXISTS postgis;\r\n");
+        }
+
+
+        for (Model model : models){
+            sql.append("\r\n");
+            sql.append(model.getTableSQL());
+        }
+        for (Model model : models){
+            String str = model.getDiamondTableSQL();
+            if (!str.isEmpty()){
+                sql.append("\r\n");
+                sql.append(str);
+            }
+        }
+
+        sql.append("\r\n\r\n");
+        for (Model model : models){
+            sql.append(model.getForeignKeySQL());
+        }
+
+        sql.append("\r\n\r\n");
+        for (Model model : models){
+            sql.append(model.getIndexSQL());
+        }
+
+        if (hasLastModifiedField){
+            sql.append("\r\n\r\n\r\n");
+            sql.append(
+                "CREATE OR REPLACE FUNCTION last_modified() RETURNS trigger AS $last_modified$\r\n" +
+                "    BEGIN\r\n" +
+                "        NEW.LAST_MODIFIED := current_timestamp;\r\n" +
+                "        RETURN NEW;\r\n" +
+                "    END;\r\n" +
+                "$last_modified$ LANGUAGE plpgsql;\r\n\r\n"
+            );
+            sql.append("\r\n\r\n");
+        }
+
+        for (Model model : models){
+            sql.append(model.getTriggerSQL());
+        }
+
+        return sql.toString();
+    }
+}