refactor: Consolidate trimming methods into trimEdges

Author: hyunmin0317

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/json/BasicJsonParser.java

@@ -52,7 +52,7 @@ public List<Object> parseList(String json) {
 
 	private List<Object> parseListInternal(int nesting, String json) {
 		List<Object> list = new ArrayList<>();
-		json = trimLeadingCharacter(trimTrailingCharacter(json, ']'), '[').trim();
+		json = trimEdges(json, '[', ']').trim();
 		for (String value : tokenize(json)) {
 			list.add(parseInternal(nesting + 1, value));
 		}
@@ -70,7 +70,7 @@ private Object parseInternal(int nesting, String json) {
 			return parseMapInternal(nesting + 1, json);
 		}
 		if (json.startsWith("\"")) {
-			return trimTrailingCharacter(trimLeadingCharacter(json, '"'), '"');
+			return trimEdges(json, '"', '"');
 		}
 		try {
 			return Long.valueOf(json);
@@ -89,12 +89,12 @@ private Object parseInternal(int nesting, String json) {
 
 	private Map<String, Object> parseMapInternal(int nesting, String json) {
 		Map<String, Object> map = new LinkedHashMap<>();
-		json = trimLeadingCharacter(trimTrailingCharacter(json, '}'), '{').trim();
+		json = trimEdges(json, '{', '}').trim();
 		for (String pair : tokenize(json)) {
 			String[] values = StringUtils.trimArrayElements(StringUtils.split(pair, ":"));
 			Assert.state(values[0].startsWith("\"") && values[0].endsWith("\""),
 					"Expecting double-quotes around field names");
-			String key = trimLeadingCharacter(trimTrailingCharacter(values[0], '"'), '"');
+			String key = trimEdges(values[0], '"', '"');
 			Object value = parseInternal(nesting, values[1]);
 			map.put(key, value);
 		}
@@ -115,6 +115,10 @@ private static String trimLeadingCharacter(String string, char c) {
 		return string;
 	}
 
+	private static String trimEdges(String string, char leadingChar, char trailingChar) {
+		return trimTrailingCharacter(trimLeadingCharacter(string, leadingChar), trailingChar);
+	}
+
 	private List<String> tokenize(String json) {
 		List<String> list = new ArrayList<>();
 		int index = 0;