code: private void generateColumnsArray(Finder<SQLProperty> entity) {
  		// generate columns array
  		Builder sp = FieldSpec.builder(ArrayTypeName.of(String.class), "COLUMNS", Modifier.STATIC, Modifier.PRIVATE,
  				Modifier.FINAL);
  		String s = "";
  		StringBuilder buffer = new StringBuilder();
  		for (SQLProperty property : entity.getCollection()) {
  			buffer.append(s + "COLUMN_" + columnNameToUpperCaseConverter.convert(property.getName()));
  			s = ", ";
  		}
  		classBuilder.addField(sp.addJavadoc("Columns array\n").initializer("{" + buffer.toString() + "}").build());
  		classBuilder.addMethod(MethodSpec.methodBuilder("columns").addModifiers(Modifier.PUBLIC)
  				.addJavadoc("Columns array\n").addAnnotation(Override.class).returns(ArrayTypeName.of(String.class))
  				.addStatement("return COLUMNS").build());
  
  		classBuilder.addMethod(MethodSpec.methodBuilder("name").addModifiers(Modifier.PUBLIC).addJavadoc("table name\n")
  				.addAnnotation(Override.class).returns(TypeName.get(String.class)).addStatement("return TABLE_NAME")
  				.build());
  	}
docs: generate columns array.
  
  @param entity
  the entity