fix: refactor to use StandardCharsets (#1243)

google-http-client/src/main/java/com/google/api/client/http/AbstractHttpContent.java

@@ -14,11 +14,11 @@
 
 package com.google.api.client.http;
 
-import com.google.api.client.util.Charsets;
 import com.google.api.client.util.IOUtils;
 import com.google.api.client.util.StreamingContent;
 import java.io.IOException;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 
 /**
  * Abstract implementation of an HTTP content with typical options.
@@ -87,13 +87,13 @@ public AbstractHttpContent setMediaType(HttpMediaType mediaType) {
   }
 
   /**
-   * Returns the charset specified in the media type or {@code Charsets#UTF_8} if not specified.
+   * Returns the charset specified in the media type or ISO_8859_1 if not specified.
    *
    * @since 1.10
    */
   protected final Charset getCharset() {
     return mediaType == null || mediaType.getCharsetParameter() == null
-        ? Charsets.ISO_8859_1
+        ? StandardCharsets.ISO_8859_1
         : mediaType.getCharsetParameter();
   }
 

google-http-client/src/main/java/com/google/api/client/http/HttpResponse.java

@@ -14,7 +14,6 @@
 
 package com.google.api.client.http;
 
-import com.google.api.client.util.Charsets;
 import com.google.api.client.util.IOUtils;
 import com.google.api.client.util.LoggingInputStream;
 import com.google.api.client.util.Preconditions;
@@ -26,6 +25,7 @@
 import java.io.OutputStream;
 import java.lang.reflect.Type;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.Locale;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -506,14 +506,14 @@ public String parseAsString() throws IOException {
   }
 
   /**
-   * Returns the {@link Charset} specified in the Content-Type of this response or the {@code
-   * "ISO-8859-1"} charset as a default.
+   * Returns the {@link Charset} specified in the Content-Type of this response or the ISO-8859-1
+   * charset as a default.
    *
    * @since 1.10
    */
   public Charset getContentCharset() {
     return mediaType == null || mediaType.getCharsetParameter() == null
-        ? Charsets.ISO_8859_1
+        ? StandardCharsets.ISO_8859_1
         : mediaType.getCharsetParameter();
   }
 }

google-http-client/src/main/java/com/google/api/client/http/UrlEncodedParser.java

@@ -15,7 +15,6 @@
 package com.google.api.client.http;
 
 import com.google.api.client.util.ArrayValueMap;
-import com.google.api.client.util.Charsets;
 import com.google.api.client.util.ClassInfo;
 import com.google.api.client.util.Data;
 import com.google.api.client.util.FieldInfo;
@@ -34,6 +33,7 @@
 import java.io.StringWriter;
 import java.lang.reflect.Type;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -72,7 +72,10 @@ public class UrlEncodedParser implements ObjectParser {
    * @since 1.13
    */
   public static final String MEDIA_TYPE =
-      new HttpMediaType(UrlEncodedParser.CONTENT_TYPE).setCharsetParameter(Charsets.UTF_8).build();
+      new HttpMediaType(UrlEncodedParser.CONTENT_TYPE)
+          .setCharsetParameter(StandardCharsets.UTF_8)
+          .build();
+
   /**
    * Parses the given URL-encoded content into the given data object of data key name/value pairs
    * using {@link #parse(Reader, Object)}.

google-http-client/src/main/java/com/google/api/client/json/JsonFactory.java

@@ -14,14 +14,14 @@
 
 package com.google.api.client.json;
 
-import com.google.api.client.util.Charsets;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.Reader;
 import java.io.Writer;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 
 /**
  * Abstract low-level JSON factory.
@@ -159,7 +159,7 @@ private String toString(Object item, boolean pretty) throws IOException {
    */
   private ByteArrayOutputStream toByteStream(Object item, boolean pretty) throws IOException {
     ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
-    JsonGenerator generator = createJsonGenerator(byteStream, Charsets.UTF_8);
+    JsonGenerator generator = createJsonGenerator(byteStream, StandardCharsets.UTF_8);
     if (pretty) {
       generator.enablePrettyPrint();
     }

google-http-client/src/main/java/com/google/api/client/testing/http/MockLowLevelHttpRequest.java

@@ -18,13 +18,13 @@
 import com.google.api.client.http.LowLevelHttpRequest;
 import com.google.api.client.http.LowLevelHttpResponse;
 import com.google.api.client.util.Beta;
-import com.google.api.client.util.Charsets;
 import com.google.api.client.util.IOUtils;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -164,7 +164,7 @@ public String getContentAsString() throws IOException {
     HttpMediaType mediaType = contentType != null ? new HttpMediaType(contentType) : null;
     Charset charset =
         mediaType == null || mediaType.getCharsetParameter() == null
-            ? Charsets.ISO_8859_1
+            ? StandardCharsets.ISO_8859_1
             : mediaType.getCharsetParameter();
     return out.toString(charset.name());
   }

google-http-client/src/test/java/com/google/api/client/http/MultipartContentTest.java

@@ -15,9 +15,9 @@
 package com.google.api.client.http;
 
 import com.google.api.client.json.Json;
-import com.google.api.client.util.Charsets;
 import com.google.api.client.util.StringUtils;
 import java.io.ByteArrayOutputStream;
+import java.nio.charset.StandardCharsets;
 import junit.framework.TestCase;
 
 /**
@@ -77,7 +77,7 @@ public void testRandomContent() throws Exception {
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     content.writeTo(out);
     String expectedContent = expectedStringBuilder.toString();
-    assertEquals(expectedContent, out.toString(Charsets.UTF_8.name()));
+    assertEquals(expectedContent, out.toString(StandardCharsets.UTF_8.name()));
     assertEquals(StringUtils.getBytesUtf8(expectedContent).length, content.getLength());
   }
 
@@ -128,7 +128,7 @@ private void subtestContent(String expectedContent, String boundaryString, Strin
     // write to string
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     content.writeTo(out);
-    assertEquals(expectedContent, out.toString(Charsets.UTF_8.name()));
+    assertEquals(expectedContent, out.toString(StandardCharsets.UTF_8.name()));
     assertEquals(StringUtils.getBytesUtf8(expectedContent).length, content.getLength());
     assertEquals(
         boundaryString == null