Add support for Charset in Quarkus Config system

core/runtime/src/main/java/io/quarkus/runtime/configuration/CharsetConverter.java

@@ -0,0 +1,28 @@
+package io.quarkus.runtime.configuration;
+
+import static io.quarkus.runtime.configuration.ConverterSupport.DEFAULT_QUARKUS_CONVERTER_PRIORITY;
+
+import java.io.Serializable;
+import java.nio.charset.Charset;
+
+import javax.annotation.Priority;
+
+import org.eclipse.microprofile.config.spi.Converter;
+
+/**
+ * A converter which converts a Charset string into an instance of {@link java.nio.charset.Charset}.
+ */
+@Priority(DEFAULT_QUARKUS_CONVERTER_PRIORITY)
+public class CharsetConverter implements Converter<Charset>, Serializable {
+
+    private static final long serialVersionUID = 2320905063828247874L;
+
+    @Override
+    public Charset convert(String value) {
+        try {
+            return Charset.forName(value);
+        } catch (Exception e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
+}

core/runtime/src/main/resources/META-INF/services/org.eclipse.microprofile.config.spi.Converter

@@ -1,4 +1,5 @@
 io.quarkus.runtime.configuration.InetSocketAddressConverter
+io.quarkus.runtime.configuration.CharsetConverter
 io.quarkus.runtime.configuration.CidrAddressConverter
 io.quarkus.runtime.configuration.InetAddressConverter
 io.quarkus.runtime.configuration.RegexConverter

core/runtime/src/test/java/io/quarkus/runtime/configuration/CharsetConverterTestCase.java

@@ -0,0 +1,39 @@
+package io.quarkus.runtime.configuration;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.nio.charset.StandardCharsets;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class CharsetConverterTestCase {
+
+    private CharsetConverter charsetConverter;
+
+    @BeforeEach
+    public void setup() {
+        charsetConverter = new CharsetConverter();
+    }
+
+    @Test
+    public void testUTF8Uppercase() {
+        assertEquals(charsetConverter.convert("UTF-8"), StandardCharsets.UTF_8);
+    }
+
+    @Test
+    public void testUTF8Lowercase() {
+        assertEquals(charsetConverter.convert("utf-8"), StandardCharsets.UTF_8);
+    }
+
+    @Test
+    public void testOther() {
+        assertEquals(charsetConverter.convert("US-ASCII"), StandardCharsets.US_ASCII);
+    }
+
+    @Test
+    public void testInvalidCharset() {
+        assertThrows(IllegalArgumentException.class, () -> charsetConverter.convert("whatever"));
+    }
+}