GH-1152: Fix Sonar issue

Author: garyrussell

spring-amqp/src/main/java/org/springframework/amqp/core/Message.java

@@ -121,10 +121,7 @@ private String getBodyContentAsString() {
 				return SerializationUtils.deserialize(new ByteArrayInputStream(this.body), whiteListPatterns,
 						ClassUtils.getDefaultClassLoader()).toString();
 			}
-			String encoding = nullProps ? null : this.messageProperties.getContentEncoding();
-			if (encoding == null) {
-				encoding = bodyEncoding;
-			}
+			String encoding = encoding(nullProps);
 			if (MessageProperties.CONTENT_TYPE_TEXT_PLAIN.equals(contentType)
 					|| MessageProperties.CONTENT_TYPE_JSON.equals(contentType)
 					|| MessageProperties.CONTENT_TYPE_JSON_ALT.equals(contentType)
@@ -139,6 +136,14 @@ private String getBodyContentAsString() {
 		return this.body.toString() + "(byte[" + this.body.length + "])"; //NOSONAR
 	}
 
+	private String encoding(boolean nullProps) {
+		String encoding = nullProps ? null : this.messageProperties.getContentEncoding();
+		if (encoding == null) {
+			encoding = bodyEncoding;
+		}
+		return encoding;
+	}
+
 	@Override
 	public int hashCode() {
 		final int prime = 31;