Added go text template writier (#1)

feat(templ): ✨ added templ to command line that reads go template and outputs code

Reviewed-on: #1
Co-authored-by: Hein <hein.puth@gmail.com>
Co-committed-by: Hein <hein.puth@gmail.com>

pkg/commontypes/java.go

@@ -0,0 +1,68 @@
+package commontypes
+
+// JavaTypeMap maps PostgreSQL types to Java types
+var JavaTypeMap = map[string]string{
+	// Integer types
+	"integer":     "Integer",
+	"int":         "Integer",
+	"int4":        "Integer",
+	"smallint":    "Short",
+	"int2":        "Short",
+	"bigint":      "Long",
+	"int8":        "Long",
+	"serial":      "Integer",
+	"bigserial":   "Long",
+	"smallserial": "Short",
+
+	// String types
+	"text":      "String",
+	"varchar":   "String",
+	"char":      "String",
+	"character": "String",
+	"citext":    "String",
+	"bpchar":    "String",
+	"uuid":      "UUID",
+
+	// Boolean
+	"boolean": "Boolean",
+	"bool":    "Boolean",
+
+	// Float types
+	"real":             "Float",
+	"float4":           "Float",
+	"double precision": "Double",
+	"float8":           "Double",
+	"numeric":          "BigDecimal",
+	"decimal":          "BigDecimal",
+
+	// Date/Time types
+	"timestamp":                   "Timestamp",
+	"timestamp without time zone": "Timestamp",
+	"timestamp with time zone":    "Timestamp",
+	"timestamptz":                 "Timestamp",
+	"date":                        "Date",
+	"time":                        "Time",
+	"time without time zone":      "Time",
+	"time with time zone":         "Time",
+	"timetz":                      "Time",
+
+	// Binary
+	"bytea": "byte[]",
+
+	// JSON
+	"json":  "String",
+	"jsonb": "String",
+}
+
+// SQLToJava converts SQL types to Java types
+func SQLToJava(sqlType string, nullable bool) string {
+	baseType := ExtractBaseType(sqlType)
+
+	javaType, ok := JavaTypeMap[baseType]
+	if !ok {
+		javaType = "Object"
+	}
+
+	// Java uses wrapper classes for nullable types by default
+	return javaType
+}