KAFKA-19137 Use StandardCharsets.UTF_8 instead of StandardCharsets.UTF_8.name() (#19464)

Replace `StandardCharsets.UTF_8.name()` with `StandardCharsets.UTF_8` to
avoid UnsupportedEncodingException and optimize the related code at the
same time.

Reviewers: Ken Huang <[email protected]>, PoAn Yang
<[email protected]>, Chia-Ping Tsai <[email protected]>

Author: xijiu

Diff for: connect/file/src/main/java/org/apache/kafka/connect/file/FileStreamSinkTask.java

@@ -69,7 +69,7 @@ public void start(Map<String, String> props) {
                 outputStream = new PrintStream(
                     Files.newOutputStream(Paths.get(filename), StandardOpenOption.CREATE, StandardOpenOption.APPEND),
                     false,
-                    StandardCharsets.UTF_8.name());
+                    StandardCharsets.UTF_8);
             } catch (IOException e) {
                 throw new ConnectException("Couldn't find or create file '" + filename + "' for FileStreamSinkTask", e);
             }

Diff for: connect/mirror/src/main/java/org/apache/kafka/connect/mirror/MirrorMaker.java

@@ -52,13 +52,11 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.File;
-import java.io.UnsupportedEncodingException;
 import java.net.InetAddress;
 import java.net.URI;
 import java.net.URLEncoder;
 import java.net.UnknownHostException;
 import java.nio.charset.StandardCharsets;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -236,14 +234,9 @@ private void checkHerder(SourceAndTarget sourceAndTarget) {
     private void addHerder(SourceAndTarget sourceAndTarget) {
         log.info("creating herder for " + sourceAndTarget.toString());
         Map<String, String> workerProps = config.workerConfig(sourceAndTarget);
-        List<String> restNamespace;
-        try {
-            String encodedSource = encodePath(sourceAndTarget.source());
-            String encodedTarget = encodePath(sourceAndTarget.target());
-            restNamespace = Arrays.asList(encodedSource, encodedTarget);
-        } catch (UnsupportedEncodingException e) {
-            throw new RuntimeException("Unable to create encoded URL paths for source and target using UTF-8", e);
-        }
+        String encodedSource = encodePath(sourceAndTarget.source());
+        String encodedTarget = encodePath(sourceAndTarget.target());
+        List<String> restNamespace = List.of(encodedSource, encodedTarget);
         String workerId = generateWorkerId(sourceAndTarget);
         Plugins plugins = new Plugins(workerProps);
         plugins.compareAndSwapWithDelegatingLoader();
@@ -282,8 +275,8 @@ private void addHerder(SourceAndTarget sourceAndTarget) {
         herders.put(sourceAndTarget, herder);
     }
 
-    private static String encodePath(String rawPath) throws UnsupportedEncodingException {
-        return URLEncoder.encode(rawPath, StandardCharsets.UTF_8.name())
+    private static String encodePath(String rawPath) {
+        return URLEncoder.encode(rawPath, StandardCharsets.UTF_8)
                 // Java's out-of-the-box URL encoder encodes spaces (' ') as pluses ('+'),
                 // and pluses as '%2B'
                 // But Jetty doesn't decode pluses at all and leaves them as-are in decoded

Diff for: connect/runtime/src/test/java/org/apache/kafka/connect/integration/RestForwardingIntegrationTest.java

@@ -215,7 +215,7 @@ public void testRestForwardToLeader(boolean dualListener, boolean followerSsl, b
                 "\"name\": \"blah\"," +
                 "\"config\": {}" +
                 "}";
-        StringEntity entity = new StringEntity(jsonBody, StandardCharsets.UTF_8.name());
+        StringEntity entity = new StringEntity(jsonBody, StandardCharsets.UTF_8);
         entity.setContentType("application/json");
         request.setEntity(entity);
         HttpResponse httpResponse = executeRequest(followerUrl, request);

Diff for: connect/runtime/src/test/java/org/apache/kafka/connect/runtime/rest/ConnectRestServerTest.java

@@ -463,7 +463,7 @@ private String executeGet(URI serverUrl, String endpoint) throws IOException {
 
     private String executePut(URI serverUrl, String endpoint, String jsonBody) throws IOException {
         HttpPut request = new HttpPut(endpoint);
-        StringEntity entity = new StringEntity(jsonBody, StandardCharsets.UTF_8.name());
+        StringEntity entity = new StringEntity(jsonBody, StandardCharsets.UTF_8);
         entity.setContentType("application/json");
         request.setEntity(entity);
         HttpResponse response = executeRequest(serverUrl, request);

Diff for: streams/src/test/java/org/apache/kafka/streams/kstream/PrintedTest.java

@@ -33,12 +33,12 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.PrintStream;
-import java.io.UnsupportedEncodingException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 public class PrintedTest {
@@ -75,34 +75,34 @@ public void shouldCreateProcessorThatPrintsToFile() throws IOException {
     }
 
     @Test
-    public void shouldCreateProcessorThatPrintsToStdOut() throws UnsupportedEncodingException {
+    public void shouldCreateProcessorThatPrintsToStdOut() {
         final ProcessorSupplier<String, Integer, Void, Void> supplier = new PrintedInternal<>(sysOutPrinter).build("processor");
         final Processor<String, Integer, Void, Void> processor = supplier.get();
 
         processor.process(new Record<>("good", 2, 0L));
         processor.close();
-        assertThat(sysOut.toString(StandardCharsets.UTF_8.name()), equalTo("[processor]: good, 2\n"));
+        assertEquals(sysOut.toString(StandardCharsets.UTF_8), "[processor]: good, 2\n");
     }
 
     @Test
-    public void shouldPrintWithLabel() throws UnsupportedEncodingException {
+    public void shouldPrintWithLabel() {
         final Processor<String, Integer, Void, Void> processor = new PrintedInternal<>(sysOutPrinter.withLabel("label"))
                 .build("processor")
                 .get();
 
         processor.process(new Record<>("hello", 3, 0L));
         processor.close();
-        assertThat(sysOut.toString(StandardCharsets.UTF_8.name()), equalTo("[label]: hello, 3\n"));
+        assertEquals(sysOut.toString(StandardCharsets.UTF_8), "[label]: hello, 3\n");
     }
 
     @Test
-    public void shouldPrintWithKeyValueMapper() throws UnsupportedEncodingException {
+    public void shouldPrintWithKeyValueMapper() {
         final Processor<String, Integer, Void, Void> processor = new PrintedInternal<>(
             sysOutPrinter.withKeyValueMapper((key, value) -> String.format("%s -> %d", key, value))
         ).build("processor").get();
         processor.process(new Record<>("hello", 1, 0L));
         processor.close();
-        assertThat(sysOut.toString(StandardCharsets.UTF_8.name()), equalTo("[processor]: hello -> 1\n"));
+        assertEquals(sysOut.toString(StandardCharsets.UTF_8), "[processor]: hello -> 1\n");
     }
 
     @Test

Diff for: tools/src/main/java/org/apache/kafka/tools/PushHttpMetricsReporter.java

@@ -235,7 +235,7 @@ static HttpURLConnection newHttpConnection(URL url) throws IOException {
 
     // Static package-private so unit tests can mock reading response
     static String readResponse(InputStream is) {
-        try (Scanner s = new Scanner(is, StandardCharsets.UTF_8.name()).useDelimiter("\\A")) {
+        try (Scanner s = new Scanner(is, StandardCharsets.UTF_8).useDelimiter("\\A")) {
             return s.hasNext() ? s.next() : "";
         }
     }

Diff for: tools/src/test/java/org/apache/kafka/tools/ConnectPluginPathTest.java

@@ -38,7 +38,6 @@
 import java.io.OutputStream;
 import java.io.PrintStream;
 import java.io.UncheckedIOException;
-import java.io.UnsupportedEncodingException;
 import java.net.MalformedURLException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -591,34 +590,30 @@ public CommandResult(int returnCode, String out, String err, PluginScanResult re
     private static CommandResult runCommand(Object... args) {
         ByteArrayOutputStream out = new ByteArrayOutputStream();
         ByteArrayOutputStream err = new ByteArrayOutputStream();
-        try {
-            int returnCode = ConnectPluginPath.mainNoExit(
-                    Arrays.stream(args)
-                            .map(Object::toString)
-                            .collect(Collectors.toList())
-                            .toArray(new String[]{}),
-                    new PrintStream(out, true, "utf-8"),
-                    new PrintStream(err, true, "utf-8"));
-            Set<Path> pluginLocations = getPluginLocations(args);
-            ClassLoader parent = ConnectPluginPath.class.getClassLoader();
-            ClassLoaderFactory factory = new ClassLoaderFactory();
-            try (DelegatingClassLoader delegatingClassLoader = factory.newDelegatingClassLoader(parent)) {
-                Set<PluginSource> sources = PluginUtils.pluginSources(pluginLocations, delegatingClassLoader, factory);
-                String stdout = new String(out.toByteArray(), StandardCharsets.UTF_8);
-                String stderr = new String(err.toByteArray(), StandardCharsets.UTF_8);
-                log.info("STDOUT:\n{}", stdout);
-                log.info("STDERR:\n{}", stderr);
-                return new CommandResult(
-                        returnCode,
-                        stdout,
-                        stderr,
-                        new ReflectionScanner().discoverPlugins(sources),
-                        new ServiceLoaderScanner().discoverPlugins(sources)
-                );
-            } catch (IOException e) {
-                throw new RuntimeException(e);
-            }
-        } catch (UnsupportedEncodingException e) {
+        int returnCode = ConnectPluginPath.mainNoExit(
+                Arrays.stream(args)
+                        .map(Object::toString)
+                        .toList()
+                        .toArray(new String[]{}),
+                new PrintStream(out, true, StandardCharsets.UTF_8),
+                new PrintStream(err, true, StandardCharsets.UTF_8));
+        Set<Path> pluginLocations = getPluginLocations(args);
+        ClassLoader parent = ConnectPluginPath.class.getClassLoader();
+        ClassLoaderFactory factory = new ClassLoaderFactory();
+        try (DelegatingClassLoader delegatingClassLoader = factory.newDelegatingClassLoader(parent)) {
+            Set<PluginSource> sources = PluginUtils.pluginSources(pluginLocations, delegatingClassLoader, factory);
+            String stdout = out.toString(StandardCharsets.UTF_8);
+            String stderr = err.toString(StandardCharsets.UTF_8);
+            log.info("STDOUT:\n{}", stdout);
+            log.info("STDERR:\n{}", stderr);
+            return new CommandResult(
+                    returnCode,
+                    stdout,
+                    stderr,
+                    new ReflectionScanner().discoverPlugins(sources),
+                    new ServiceLoaderScanner().discoverPlugins(sources)
+            );
+        } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }