Avoid ByteArrayOutputStream for source values without the need to be encoded

Closes gh-24154

Author: jhoeller

spring-web/src/main/java/org/springframework/web/util/HierarchicalUriComponents.java

@@ -335,8 +335,21 @@ static String encodeUriComponent(String source, Charset charset, Type type) {
 		Assert.notNull(type, "Type must not be null");
 
 		byte[] bytes = source.getBytes(charset);
+		boolean original = true;
+		for (byte b : bytes) {
+			if (b < 0) {
+				b += 256;
+			}
+			if (!type.isAllowed(b)) {
+				original = false;
+				break;
+			}
+		}
+		if (original) {
+			return source;
+		}
+
 		ByteArrayOutputStream bos = new ByteArrayOutputStream(bytes.length);
-		boolean changed = false;
 		for (byte b : bytes) {
 			if (b < 0) {
 				b += 256;
@@ -350,10 +363,9 @@ static String encodeUriComponent(String source, Charset charset, Type type) {
 				char hex2 = Character.toUpperCase(Character.forDigit(b & 0xF, 16));
 				bos.write(hex1);
 				bos.write(hex2);
-				changed = true;
 			}
 		}
-		return (changed ? new String(bos.toByteArray(), charset) : source);
+		return new String(bos.toByteArray(), charset);
 	}
 
 	private Type getHostType() {
@@ -416,7 +428,6 @@ else if (!type.isAllowed(ch)) {
 
 	@Override
 	protected HierarchicalUriComponents expandInternal(UriTemplateVariables uriVariables) {
-
 		Assert.state(!this.encodeState.equals(EncodeState.FULLY_ENCODED),
 				"URI components already encoded, and could not possibly contain '{' or '}'.");