improve: prices now can use a decimal comma as a separator

Fix #1513

Author: php-coder

src/main/java/ru/mystamps/web/config/MvcConfig.java

@@ -61,6 +61,7 @@
 import ru.mystamps.web.feature.site.ResourceUrl;
 import ru.mystamps.web.feature.site.SiteConfig;
 import ru.mystamps.web.feature.site.SiteUrl;
+import ru.mystamps.web.support.spring.mvc.BigDecimalConverter;
 import ru.mystamps.web.support.spring.mvc.RestExceptionHandler;
 import ru.mystamps.web.support.spring.security.CurrentUserArgumentResolver;
 
@@ -95,6 +96,7 @@ public class MvcConfig implements WebMvcConfigurer {
 	public void addFormatters(FormatterRegistry registry) {
 		registry.addConverter(new CategoryLinkEntityDtoConverter(categoryService));
 		registry.addConverter(new CountryLinkEntityDtoConverter(countryService));
+		registry.addConverter(new BigDecimalConverter());
 	}
 
 	@Override

src/main/java/ru/mystamps/web/support/spring/mvc/BigDecimalConverter.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2009-2021 Slava Semushin <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+package ru.mystamps.web.support.spring.mvc;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.core.convert.converter.Converter;
+
+import java.math.BigDecimal;
+
+// @todo #1513 Add integration test to check that prices accept a decimal comma
+// CheckStyle: ignore LineLength for next 2 lines
+/**
+ * Converter for BigDecimal that correctly parse values with a comma separator (in addition to a point).
+ */
+public class BigDecimalConverter implements Converter<String, BigDecimal> {
+	
+	@Override
+	public BigDecimal convert(String source) {
+		if (StringUtils.EMPTY.equals(source)) {
+			return null;
+		}
+		
+		String value = source;
+		if (source.indexOf(',') >= 0) {
+			// "10,5" => "10.5"
+			value = source.replace(',', '.');
+		}
+		
+		return new BigDecimal(value);
+	}
+	
+}