Add parse overload which fails on invalid inputs

okhttp-android-support/src/test/java/okhttp3/internal/huc/JavaApiConverterTest.java

@@ -660,7 +660,7 @@ public class JavaApiConverterTest {
   }
 
   private static RequestBody createRequestBody(String bodyText) {
-    return RequestBody.create(MediaType.parse("text/plain"), bodyText);
+    return RequestBody.create(MediaType.get("text/plain"), bodyText);
   }
 
   private static ResponseBody createResponseBody(String bodyText) {
@@ -668,7 +668,7 @@ public class JavaApiConverterTest {
     final long contentLength = source.size();
     return new ResponseBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain; charset=utf-8");
+        return MediaType.get("text/plain; charset=utf-8");
       }
 
       @Override public long contentLength() {

okhttp-apache/src/main/java/okhttp3/apache/HttpEntityBody.java

@@ -8,7 +8,7 @@ import org.apache.http.HttpEntity;
 
 /** Adapts an {@link HttpEntity} to OkHttp's {@link RequestBody}. */
 final class HttpEntityBody extends RequestBody {
-  private static final MediaType DEFAULT_MEDIA_TYPE = MediaType.parse("application/octet-stream");
+  private static final MediaType DEFAULT_MEDIA_TYPE = MediaType.get("application/octet-stream");
 
   private final HttpEntity entity;
   private final MediaType mediaType;

okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsOverHttps.java

@@ -53,8 +53,8 @@ import okio.ByteString;
  * Until then, expect API and behavior changes when you update your OkHttp dependency.</strong>
  */
 public class DnsOverHttps implements Dns {
-  public static final MediaType DNS_MESSAGE = MediaType.parse("application/dns-message");
+  public static final MediaType DNS_MESSAGE = MediaType.get("application/dns-message");
-  public static final MediaType UDPWIREFORMAT = MediaType.parse("application/dns-udpwireformat");
+  public static final MediaType UDPWIREFORMAT = MediaType.get("application/dns-udpwireformat");
   public static final int MAX_RESPONSE_SIZE = 64 * 1024;
   private final OkHttpClient client;
   private final HttpUrl url;

okhttp-logging-interceptor/src/test/java/okhttp3/logging/HttpLoggingInterceptorTest.java

@@ -53,7 +53,7 @@ import static org.junit.Assert.fail;
 import static org.junit.Assume.assumeThat;
 
 public final class HttpLoggingInterceptorTest {
-  private static final MediaType PLAIN = MediaType.parse("text/plain; charset=utf-8");
+  private static final MediaType PLAIN = MediaType.get("text/plain; charset=utf-8");
 
   @Rule public final MockWebServer server = new MockWebServer();
 

okhttp-tests/src/test/java/okhttp3/CacheTest.java

@@ -774,7 +774,7 @@ public final class CacheTest {
 
   private RequestBody requestBodyOrNull(String requestMethod) {
     return (requestMethod.equals("POST") || requestMethod.equals("PUT"))
-        ? RequestBody.create(MediaType.parse("text/plain"), "foo")
+        ? RequestBody.create(MediaType.get("text/plain"), "foo")
         : null;
   }
 
@@ -862,7 +862,7 @@ public final class CacheTest {
 
     Request request = new Request.Builder()
         .url(url)
-        .put(RequestBody.create(MediaType.parse("text/plain"), "foo"))
+        .put(RequestBody.create(MediaType.get("text/plain"), "foo"))
         .build();
     Response invalidate = client.newCall(request).execute();
     assertEquals("", invalidate.body().string());

okhttp-tests/src/test/java/okhttp3/CallTest.java

@@ -206,7 +206,7 @@ public final class CallTest {
     server.enqueue(new MockResponse());
 
     try {
-      new Request.Builder().method("GET", RequestBody.create(MediaType.parse("text/plain"), "abc"));
+      new Request.Builder().method("GET", RequestBody.create(MediaType.get("text/plain"), "abc"));
       fail();
     } catch (IllegalArgumentException expected) {
     }
@@ -300,7 +300,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
 
     executeSynchronously(request)
@@ -501,7 +501,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .method("DELETE", RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .method("DELETE", RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
 
     executeSynchronously(request)
@@ -518,7 +518,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .put(RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .put(RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
 
     executeSynchronously(request)
@@ -547,7 +547,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .patch(RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .patch(RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
 
     executeSynchronously(request)
@@ -576,7 +576,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .method("CUSTOM", RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .method("CUSTOM", RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
 
     executeSynchronously(request)
@@ -937,7 +937,7 @@ public final class CallTest {
     // Call 1: set a deadline on the request body.
     RequestBody requestBody1 = new RequestBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain");
+        return MediaType.get("text/plain");
       }
 
       @Override public void writeTo(BufferedSink sink) throws IOException {
@@ -955,7 +955,7 @@ public final class CallTest {
     // Call 2: check for the absence of a deadline on the request body.
     RequestBody requestBody2 = new RequestBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain");
+        return MediaType.get("text/plain");
       }
 
       @Override public void writeTo(BufferedSink sink) throws IOException {
@@ -1272,7 +1272,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "def"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "def"))
         .build();
     client.newCall(request).enqueue(callback);
 
@@ -1298,7 +1298,7 @@ public final class CallTest {
 
     Request request2 = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "body!"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "body!"))
         .build();
     Response response2 = client.newCall(request2).execute();
     assertEquals("def", response2.body().string());
@@ -1614,7 +1614,7 @@ public final class CallTest {
 
     Response response = client.newCall(new Request.Builder()
         .url(server.url("/page1"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "Request Body"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "Request Body"))
         .build()).execute();
     assertEquals("Page 2", response.body().string());
 
@@ -1668,7 +1668,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "Hello"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "Hello"))
         .build();
     Response response = client.newCall(request).execute();
 
@@ -1777,7 +1777,7 @@ public final class CallTest {
     // when
     Response response = client.newCall(new Request.Builder()
         .url(server.url("/page1"))
-        .method("PROPFIND", RequestBody.create(MediaType.parse("text/plain"), "Request Body"))
+        .method("PROPFIND", RequestBody.create(MediaType.get("text/plain"), "Request Body"))
         .build()).execute();
 
     // then
@@ -2408,7 +2408,7 @@ public final class CallTest {
     Request request = new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     executeSynchronously(request)
@@ -2424,7 +2424,7 @@ public final class CallTest {
     Request request = new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), ""))
+        .post(RequestBody.create(MediaType.get("text/plain"), ""))
         .build();
 
     executeSynchronously(request)
@@ -2448,7 +2448,7 @@ public final class CallTest {
     Request request = new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     Call call = client.newCall(request);
@@ -2473,7 +2473,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     executeSynchronously(request)
@@ -2499,7 +2499,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     Call call = client.newCall(request);
@@ -2526,7 +2526,7 @@ public final class CallTest {
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build());
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
@@ -2548,7 +2548,7 @@ public final class CallTest {
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build());
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
@@ -2567,7 +2567,7 @@ public final class CallTest {
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
         .header("Expect", "100-continue")
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build());
     executeSynchronously(new Request.Builder()
         .url(server.url("/"))
@@ -2972,7 +2972,7 @@ public final class CallTest {
 
     Request request = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     executeSynchronously(request);
@@ -3064,7 +3064,7 @@ public final class CallTest {
 
     return new RequestBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain; charset=utf-8");
+        return MediaType.get("text/plain; charset=utf-8");
       }
 
       @Override public long contentLength() throws IOException {

okhttp-tests/src/test/java/okhttp3/ConnectionReuseTest.java

@@ -191,7 +191,7 @@ public final class ConnectionReuseTest {
 
     Request requestB = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), "b"))
+        .post(RequestBody.create(MediaType.get("text/plain"), "b"))
         .build();
     Response responseB = client.newCall(requestB).execute();
     assertEquals("b", responseB.body().string());

okhttp-tests/src/test/java/okhttp3/EventListenerTest.java

@@ -970,7 +970,7 @@ public final class EventListenerTest {
     // Stream a 8 MiB body so the disconnect will happen before the server has read everything.
     RequestBody requestBody = new RequestBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain");
+        return MediaType.get("text/plain");
       }
 
       @Override public long contentLength() {
@@ -1005,26 +1005,26 @@ public final class EventListenerTest {
   @Test public void requestBodySuccessHttp1OverHttps() throws IOException {
     enableTlsWithTunnel(false);
     server.setProtocols(Arrays.asList(Protocol.HTTP_1_1));
-    requestBodySuccess(RequestBody.create(MediaType.parse("text/plain"), "Hello"), equalTo(5L),
+    requestBodySuccess(RequestBody.create(MediaType.get("text/plain"), "Hello"), equalTo(5L),
         equalTo(19L));
   }
 
   @Test public void requestBodySuccessHttp2OverHttps() throws IOException {
     enableTlsWithTunnel(false);
     server.setProtocols(Arrays.asList(Protocol.HTTP_2, Protocol.HTTP_1_1));
-    requestBodySuccess(RequestBody.create(MediaType.parse("text/plain"), "Hello"), equalTo(5L),
+    requestBodySuccess(RequestBody.create(MediaType.get("text/plain"), "Hello"), equalTo(5L),
         equalTo(19L));
   }
 
   @Test public void requestBodySuccessHttp() throws IOException {
-    requestBodySuccess(RequestBody.create(MediaType.parse("text/plain"), "Hello"), equalTo(5L),
+    requestBodySuccess(RequestBody.create(MediaType.get("text/plain"), "Hello"), equalTo(5L),
         equalTo(19L));
   }
 
   @Test public void requestBodySuccessStreaming() throws IOException {
     RequestBody requestBody = new RequestBody() {
       @Override public MediaType contentType() {
-        return MediaType.parse("text/plain");
+        return MediaType.get("text/plain");
       }
 
       @Override public void writeTo(BufferedSink sink) throws IOException {
@@ -1037,7 +1037,7 @@ public final class EventListenerTest {
   }
 
   @Test public void requestBodySuccessEmpty() throws IOException {
-    requestBodySuccess(RequestBody.create(MediaType.parse("text/plain"), ""), equalTo(0L),
+    requestBodySuccess(RequestBody.create(MediaType.get("text/plain"), ""), equalTo(0L),
         equalTo(19L));
   }
 

okhttp-tests/src/test/java/okhttp3/InterceptorTest.java

@@ -67,7 +67,7 @@ public final class InterceptorTest {
         .protocol(Protocol.HTTP_1_1)
         .code(200)
         .message("Intercepted!")
-        .body(ResponseBody.create(MediaType.parse("text/plain; charset=utf-8"), "abc"))
+        .body(ResponseBody.create(MediaType.get("text/plain; charset=utf-8"), "abc"))
         .build();
 
     client = client.newBuilder()
@@ -91,7 +91,7 @@ public final class InterceptorTest {
             .protocol(Protocol.HTTP_1_1)
             .code(200)
             .message("Intercepted!")
-            .body(ResponseBody.create(MediaType.parse("text/plain; charset=utf-8"), "abc"))
+            .body(ResponseBody.create(MediaType.get("text/plain; charset=utf-8"), "abc"))
             .build();
       }
     };
@@ -234,7 +234,7 @@ public final class InterceptorTest {
     Interceptor interceptor = new Interceptor() {
       @Override public Response intercept(Chain chain) throws IOException {
         Request originalRequest = chain.request();
-        MediaType mediaType = MediaType.parse("text/plain");
+        MediaType mediaType = MediaType.get("text/plain");
         RequestBody body = RequestBody.create(mediaType, "abc");
         return chain.proceed(originalRequest.newBuilder()
             .method("POST", body)
@@ -283,7 +283,7 @@ public final class InterceptorTest {
     Request request = new Request.Builder()
         .url(server.url("/"))
         .addHeader("Original-Header", "foo")
-        .method("PUT", RequestBody.create(MediaType.parse("text/plain"), "abc"))
+        .method("PUT", RequestBody.create(MediaType.get("text/plain"), "abc"))
         .build();
 
     client.newCall(request).execute();
@@ -818,7 +818,7 @@ public final class InterceptorTest {
     byte[] data = new byte[2 * 1024 * 1024]; // 2 MiB.
     Request request1 = new Request.Builder()
         .url(server.url("/"))
-        .post(RequestBody.create(MediaType.parse("text/plain"), data))
+        .post(RequestBody.create(MediaType.get("text/plain"), data))
         .build();
     Call call = client.newCall(request1);
 

okhttp-tests/src/test/java/okhttp3/MediaTypeTest.java

@@ -17,12 +17,17 @@
 package okhttp3;
 
 import java.nio.charset.Charset;
+import java.util.Arrays;
+import java.util.Collection;
 import okhttp3.internal.Util;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 /**
  * Test MediaType API and parsing.
@@ -30,16 +35,34 @@ import static org.junit.Assert.assertTrue;
  * <p>This test includes tests from <a href="https://code.google.com/p/guava-libraries/">Guava's</a>
  * MediaTypeTest.
  */
+@RunWith(Parameterized.class)
 public class MediaTypeTest {
+  @Parameterized.Parameters(name = "Use get = {0}")
+  public static Collection<Object[]> parameters() {
+    return Arrays.asList(
+        new Object[] { true },
+        new Object[] { false }
+    );
+  }
+
+  @Parameterized.Parameter
+  public boolean useGet;
+
+  private MediaType parse(String string) {
+    return useGet
+        ? MediaType.get(string)
+        : MediaType.parse(string);
+  }
+
   @Test public void testParse() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;boundary=foo;charset=utf-8");
+    MediaType mediaType = parse("text/plain;boundary=foo;charset=utf-8");
     assertEquals("text", mediaType.type());
     assertEquals("plain", mediaType.subtype());
     assertEquals("UTF-8", mediaType.charset().name());
     assertEquals("text/plain;boundary=foo;charset=utf-8", mediaType.toString());
-    assertTrue(mediaType.equals(MediaType.parse("text/plain;boundary=foo;charset=utf-8")));
+    assertTrue(mediaType.equals(parse("text/plain;boundary=foo;charset=utf-8")));
     assertEquals(mediaType.hashCode(),
-        MediaType.parse("text/plain;boundary=foo;charset=utf-8").hashCode());
+        parse("text/plain;boundary=foo;charset=utf-8").hashCode());
   }
 
   @Test public void testValidParse() throws Exception {
@@ -61,75 +84,86 @@ public class MediaTypeTest {
   }
 
   @Test public void testInvalidParse() throws Exception {
-    assertInvalid("");
+    assertInvalid("", "No subtype found for: \"\"");
-    assertInvalid("/");
+    assertInvalid("/", "No subtype found for: \"/\"");
-    assertInvalid("/");
+    assertInvalid("text", "No subtype found for: \"text\"");
-    assertInvalid("text");
+    assertInvalid("text/", "No subtype found for: \"text/\"");
-    assertInvalid("text/");
+    assertInvalid("te<t/plain", "No subtype found for: \"te<t/plain\"");
-    assertInvalid("te<t/plain");
+    assertInvalid(" text/plain", "No subtype found for: \" text/plain\"");
-    assertInvalid("text/pl@in");
+    assertInvalid("te xt/plain", "No subtype found for: \"te xt/plain\"");
-    assertInvalid("text/plain; a");
+    assertInvalid("text /plain", "No subtype found for: \"text /plain\"");
-    assertInvalid("text/plain; a=");
+    assertInvalid("text/ plain", "No subtype found for: \"text/ plain\"");
-    assertInvalid("text/plain; a=@");
+
-    assertInvalid("text/plain; a=\"@");
+    assertInvalid("text/pl@in",
-    assertInvalid("text/plain; a=1; b");
+        "Parameter is not formatted correctly: \"@in\" for: \"text/pl@in\"");
-    assertInvalid("text/plain; a=1; b=");
+    assertInvalid("text/plain; a",
-    assertInvalid("text/plain; a=\u2025");
+        "Parameter is not formatted correctly: \"a\" for: \"text/plain; a\"");
-    assertInvalid(" text/plain");
+    assertInvalid("text/plain; a=",
-    assertInvalid("te xt/plain");
+        "Parameter is not formatted correctly: \"a=\" for: \"text/plain; a=\"");
-    assertInvalid("text /plain");
+    assertInvalid("text/plain; a=@",
-    assertInvalid("text/ plain");
+        "Parameter is not formatted correctly: \"a=@\" for: \"text/plain; a=@\"");
-    assertInvalid("text/pl ain");
+    assertInvalid("text/plain; a=\"@",
-    assertInvalid("text/plain ");
+        "Parameter is not formatted correctly: \"a=\"@\" for: \"text/plain; a=\"@\"");
-    assertInvalid("text/plain ; a=1");
+    assertInvalid("text/plain; a=1; b",
+        "Parameter is not formatted correctly: \"b\" for: \"text/plain; a=1; b\"");
+    assertInvalid("text/plain; a=1; b=",
+        "Parameter is not formatted correctly: \"b=\" for: \"text/plain; a=1; b=\"");
+    assertInvalid("text/plain; a=\u2025",
+        "Parameter is not formatted correctly: \"a=‥\" for: \"text/plain; a=‥\"");
+    assertInvalid("text/pl ain",
+        "Parameter is not formatted correctly: \" ain\" for: \"text/pl ain\"");
+    assertInvalid("text/plain ",
+        "Parameter is not formatted correctly: \" \" for: \"text/plain \"");
+    assertInvalid("text/plain ; a=1",
+        "Parameter is not formatted correctly: \" ; a=1\" for: \"text/plain ; a=1\"");
   }
 
   @Test public void testDoubleQuotesAreSpecial() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;a=\";charset=utf-8;b=\"");
+    MediaType mediaType = parse("text/plain;a=\";charset=utf-8;b=\"");
     assertNull(mediaType.charset());
   }
 
   @Test public void testSingleQuotesAreNotSpecial() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;a=';charset=utf-8;b='");
+    MediaType mediaType = parse("text/plain;a=';charset=utf-8;b='");
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
   @Test public void testParseWithSpecialCharacters() throws Exception {
-    MediaType mediaType = MediaType.parse(
+    MediaType mediaType = parse("!#$%&'*+-.{|}~/!#$%&'*+-.{|}~; !#$%&'*+-.{|}~=!#$%&'*+-.{|}~");
-        "!#$%&'*+-.{|}~/!#$%&'*+-.{|}~; !#$%&'*+-.{|}~=!#$%&'*+-.{|}~");
     assertEquals("!#$%&'*+-.{|}~", mediaType.type());
     assertEquals("!#$%&'*+-.{|}~", mediaType.subtype());
   }
 
   @Test public void testCharsetIsOneOfManyParameters() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;a=1;b=2;charset=utf-8;c=3");
+    MediaType mediaType = parse("text/plain;a=1;b=2;charset=utf-8;c=3");
     assertEquals("text", mediaType.type());
     assertEquals("plain", mediaType.subtype());
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
   @Test public void testCharsetAndQuoting() throws Exception {
-    MediaType mediaType = MediaType.parse(
+    MediaType mediaType = parse(
         "text/plain;a=\";charset=us-ascii\";charset=\"utf-8\";b=\"iso-8859-1\"");
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
   @Test public void testDuplicatedCharsets() {
-    MediaType mediaType = MediaType.parse("text/plain; charset=utf-8; charset=UTF-8");
+    MediaType mediaType = parse("text/plain; charset=utf-8; charset=UTF-8");
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
   @Test public void testMultipleCharsets() {
-    assertNull(MediaType.parse("text/plain; charset=utf-8; charset=utf-16"));
+    assertInvalid("text/plain; charset=utf-8; charset=utf-16",
+        "Multiple charsets defined: \"utf-8\" and: \"utf-16\" for: \"text/plain; charset=utf-8; charset=utf-16\"");
   }
 
   @Test public void testIllegalCharsetName() {
-    MediaType mediaType = MediaType.parse("text/plain; charset=\"!@#$%^&*()\"");
+    MediaType mediaType = parse("text/plain; charset=\"!@#$%^&*()\"");
     assertNull(mediaType.charset());
   }
 
   @Test public void testUnsupportedCharset() {
-    MediaType mediaType = MediaType.parse("text/plain; charset=utf-wtf");
+    MediaType mediaType = parse("text/plain; charset=utf-wtf");
     assertNull(mediaType.charset());
   }
 
@@ -138,32 +172,32 @@ public class MediaTypeTest {
    * unpleasant IllegalCharsetNameException.
    */
   @Test public void testCharsetNameIsSingleQuoted() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;charset='utf-8'");
+    MediaType mediaType = parse("text/plain;charset='utf-8'");
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
   @Test public void testCharsetNameIsDoubleQuotedAndSingleQuoted() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;charset=\"'utf-8'\"");
+    MediaType mediaType = parse("text/plain;charset=\"'utf-8'\"");
     assertNull(mediaType.charset());
   }
 
   @Test public void testCharsetNameIsDoubleQuotedSingleQuote() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;charset=\"'\"");
+    MediaType mediaType = parse("text/plain;charset=\"'\"");
     assertNull(mediaType.charset());
   }
 
   @Test public void testDefaultCharset() throws Exception {
-    MediaType noCharset = MediaType.parse("text/plain");
+    MediaType noCharset = parse("text/plain");
     assertEquals("UTF-8", noCharset.charset(Util.UTF_8).name());
     assertEquals("US-ASCII", noCharset.charset(Charset.forName("US-ASCII")).name());
 
-    MediaType charset = MediaType.parse("text/plain; charset=iso-8859-1");
+    MediaType charset = parse("text/plain; charset=iso-8859-1");
     assertEquals("ISO-8859-1", charset.charset(Util.UTF_8).name());
     assertEquals("ISO-8859-1", charset.charset(Charset.forName("US-ASCII")).name());
   }
 
   @Test public void testParseDanglingSemicolon() throws Exception {
-    MediaType mediaType = MediaType.parse("text/plain;");
+    MediaType mediaType = parse("text/plain;");
     assertEquals("text", mediaType.type());
     assertEquals("plain", mediaType.subtype());
     assertNull(mediaType.charset());
@@ -171,11 +205,19 @@ public class MediaTypeTest {
   }
 
   private void assertMediaType(String string) {
-    MediaType mediaType = MediaType.parse(string);
+    assertEquals(string, parse(string).toString());
-    assertEquals(string, mediaType.toString());
   }
 
-  private void assertInvalid(String string) {
+  private void assertInvalid(String string, String exceptionMessage) {
-    assertNull(string, MediaType.parse(string));
+    if (useGet) {
+      try {
+        parse(string);
+        fail("Expected get of \"" + string + "\" to throw with: " + exceptionMessage);
+      } catch (IllegalArgumentException e) {
+        assertEquals(exceptionMessage, e.getMessage());
+      }
+    } else {
+      assertNull(string, parse(string));
+    }
   }
 }

okhttp-tests/src/test/java/okhttp3/MultipartBodyTest.java

@@ -129,13 +129,13 @@ public final class MultipartBodyTest {
                 .addPart(
                     Headers.of("Content-Disposition", "file; filename=\"file1.txt\""),
                     RequestBody.create(
-                        MediaType.parse("text/plain"), "... contents of file1.txt ..."))
+                        MediaType.get("text/plain"), "... contents of file1.txt ..."))
                 .addPart(
                     Headers.of(
                         "Content-Disposition", "file; filename=\"file2.gif\"",
                         "Content-Transfer-Encoding", "binary"),
                     RequestBody.create(
-                        MediaType.parse("image/gif"),
+                        MediaType.get("image/gif"),
                         "... contents of file2.gif ...".getBytes(UTF_8)))
                 .build())
         .build();
@@ -180,7 +180,7 @@ public final class MultipartBodyTest {
     MultipartBody body = new MultipartBody.Builder("AaB03x")
         .setType(MultipartBody.FORM)
         .addFormDataPart("field with spaces", "filename with spaces.txt",
-            RequestBody.create(MediaType.parse("text/plain; charset=utf-8"), "okay"))
+            RequestBody.create(MediaType.get("text/plain; charset=utf-8"), "okay"))
         .addFormDataPart("field with \"", "\"")
         .addFormDataPart("field with %22", "%22")
         .addFormDataPart("field with \u0391", "Alpha")

okhttp-tests/src/test/java/okhttp3/RequestTest.java

@@ -31,7 +31,7 @@ import static org.junit.Assert.fail;
 
 public final class RequestTest {
   @Test public void string() throws Exception {
-    MediaType contentType = MediaType.parse("text/plain; charset=utf-8");
+    MediaType contentType = MediaType.get("text/plain; charset=utf-8");
     RequestBody body = RequestBody.create(contentType, "abc".getBytes(Util.UTF_8));
     assertEquals(contentType, body.contentType());
     assertEquals(3, body.contentLength());
@@ -40,15 +40,15 @@ public final class RequestTest {
   }
 
   @Test public void stringWithDefaultCharsetAdded() throws Exception {
-    MediaType contentType = MediaType.parse("text/plain");
+    MediaType contentType = MediaType.get("text/plain");
     RequestBody body = RequestBody.create(contentType, "\u0800");
-    assertEquals(MediaType.parse("text/plain; charset=utf-8"), body.contentType());
+    assertEquals(MediaType.get("text/plain; charset=utf-8"), body.contentType());
     assertEquals(3, body.contentLength());
     assertEquals("e0a080", bodyToHex(body));
   }
 
   @Test public void stringWithNonDefaultCharsetSpecified() throws Exception {
-    MediaType contentType = MediaType.parse("text/plain; charset=utf-16be");
+    MediaType contentType = MediaType.get("text/plain; charset=utf-16be");
     RequestBody body = RequestBody.create(contentType, "\u0800");
     assertEquals(contentType, body.contentType());
     assertEquals(2, body.contentLength());
@@ -56,7 +56,7 @@ public final class RequestTest {
   }
 
   @Test public void byteArray() throws Exception {
-    MediaType contentType = MediaType.parse("text/plain");
+    MediaType contentType = MediaType.get("text/plain");
     RequestBody body = RequestBody.create(contentType, "abc".getBytes(Util.UTF_8));
     assertEquals(contentType, body.contentType());
     assertEquals(3, body.contentLength());
@@ -65,7 +65,7 @@ public final class RequestTest {
   }
 
   @Test public void byteArrayRange() throws Exception {
-    MediaType contentType = MediaType.parse("text/plain");
+    MediaType contentType = MediaType.get("text/plain");
     RequestBody body = RequestBody.create(contentType, ".abcd".getBytes(Util.UTF_8), 1, 3);
     assertEquals(contentType, body.contentType());
     assertEquals(3, body.contentLength());
@@ -79,7 +79,7 @@ public final class RequestTest {
     writer.write("abc");
     writer.close();
 
-    MediaType contentType = MediaType.parse("text/plain");
+    MediaType contentType = MediaType.get("text/plain");
     RequestBody body = RequestBody.create(contentType, file);
     assertEquals(contentType, body.contentType());
     assertEquals(3, body.contentLength());
@@ -89,7 +89,7 @@ public final class RequestTest {
 
   /** Common verbs used for apis such as GitHub, AWS, and Google Cloud. */
   @Test public void crudVerbs() throws IOException {
-    MediaType contentType = MediaType.parse("application/json");
+    MediaType contentType = MediaType.get("application/json");
     RequestBody body = RequestBody.create(contentType, "{}");
 
     Request get = new Request.Builder().url("http://localhost/api").get().build();

okhttp-tests/src/test/java/okhttp3/ResponseBodyTest.java

@@ -396,7 +396,7 @@ public final class ResponseBodyTest {
   }
 
   static ResponseBody body(String hex, String charset) {
-    MediaType mediaType = charset == null ? null : MediaType.parse("any/thing; charset=" + charset);
+    MediaType mediaType = charset == null ? null : MediaType.get("any/thing; charset=" + charset);
     return ResponseBody.create(mediaType, ByteString.decodeHex(hex));
   }
 

okhttp-tests/src/test/java/okhttp3/internal/http2/HttpOverHttp2Test.java

@@ -194,7 +194,7 @@ public final class HttpOverHttp2Test {
         .url(server.url("/foo"))
         .post(new RequestBody() {
           @Override public MediaType contentType() {
-            return MediaType.parse("text/plain; charset=utf-8");
+            return MediaType.get("text/plain; charset=utf-8");
           }
 
           @Override public void writeTo(BufferedSink sink) throws IOException {
@@ -221,7 +221,7 @@ public final class HttpOverHttp2Test {
         .url(server.url("/foo"))
         .post(new RequestBody() {
           @Override public MediaType contentType() {
-            return MediaType.parse("text/plain; charset=utf-8");
+            return MediaType.get("text/plain; charset=utf-8");
           }
 
           @Override public long contentLength() throws IOException {
@@ -252,7 +252,7 @@ public final class HttpOverHttp2Test {
         .url(server.url("/foo"))
         .post(new RequestBody() {
           @Override public MediaType contentType() {
-            return MediaType.parse("text/plain; charset=utf-8");
+            return MediaType.get("text/plain; charset=utf-8");
           }
 
           @Override public long contentLength() throws IOException {

okhttp/src/main/java/okhttp3/FormBody.java

@@ -28,8 +28,7 @@ import static okhttp3.HttpUrl.FORM_ENCODE_SET;
 import static okhttp3.HttpUrl.percentDecode;
 
 public final class FormBody extends RequestBody {
-  private static final MediaType CONTENT_TYPE =
+  private static final MediaType CONTENT_TYPE = MediaType.get("application/x-www-form-urlencoded");
-      MediaType.parse("application/x-www-form-urlencoded");
 
   private final List<String> encodedNames;
   private final List<String> encodedValues;

okhttp/src/main/java/okhttp3/MediaType.java

@@ -45,12 +45,15 @@ public final class MediaType {
   }
 
   /**
-   * Returns a media type for {@code string}, or null if {@code string} is not a well-formed media
+   * Returns a media type for {@code string}.
-   * type.
+   *
+   * @throws IllegalArgumentException if {@code string} is not a well-formed media type.
    */
-  public static @Nullable MediaType parse(String string) {
+  public static MediaType get(String string) {
     Matcher typeSubtype = TYPE_SUBTYPE.matcher(string);
-    if (!typeSubtype.lookingAt()) return null;
+    if (!typeSubtype.lookingAt()) {
+      throw new IllegalArgumentException("No subtype found for: \"" + string + '"');
+    }
     String type = typeSubtype.group(1).toLowerCase(Locale.US);
     String subtype = typeSubtype.group(2).toLowerCase(Locale.US);
 
@@ -58,7 +61,13 @@ public final class MediaType {
     Matcher parameter = PARAMETER.matcher(string);
     for (int s = typeSubtype.end(); s < string.length(); s = parameter.end()) {
       parameter.region(s, string.length());
-      if (!parameter.lookingAt()) return null; // This is not a well-formed media type.
+      if (!parameter.lookingAt()) {
+        throw new IllegalArgumentException("Parameter is not formatted correctly: \""
+            + string.substring(s)
+            + "\" for: \""
+            + string
+            + '"');
+      }
 
       String name = parameter.group(1);
       if (name == null || !name.equalsIgnoreCase("charset")) continue;
@@ -74,7 +83,13 @@ public final class MediaType {
         charsetParameter = parameter.group(3);
       }
       if (charset != null && !charsetParameter.equalsIgnoreCase(charset)) {
-        return null; // Multiple different charsets!
+        throw new IllegalArgumentException("Multiple charsets defined: \""
+            + charset
+            + "\" and: \""
+            + charsetParameter
+            + "\" for: \""
+            + string
+            + '"');
       }
       charset = charsetParameter;
     }
@@ -82,6 +97,18 @@ public final class MediaType {
     return new MediaType(string, type, subtype, charset);
   }
 
+  /**
+   * Returns a media type for {@code string}, or null if {@code string} is not a well-formed media
+   * type.
+   */
+  public static @Nullable MediaType parse(String string) {
+    try {
+      return get(string);
+    } catch (IllegalArgumentException ignored) {
+      return null;
+    }
+  }
+
   /**
    * Returns the high-level media type, such as "text", "image", "audio", "video", or
    * "application".

okhttp/src/main/java/okhttp3/MultipartBody.java

@@ -32,34 +32,34 @@ public final class MultipartBody extends RequestBody {
    * need to be bundled in a particular order. Any "multipart" subtypes that an implementation does
    * not recognize must be treated as being of subtype "mixed".
    */
-  public static final MediaType MIXED = MediaType.parse("multipart/mixed");
+  public static final MediaType MIXED = MediaType.get("multipart/mixed");
 
   /**
    * The "multipart/alternative" type is syntactically identical to "multipart/mixed", but the
    * semantics are different. In particular, each of the body parts is an "alternative" version of
    * the same information.
    */
-  public static final MediaType ALTERNATIVE = MediaType.parse("multipart/alternative");
+  public static final MediaType ALTERNATIVE = MediaType.get("multipart/alternative");
 
   /**
    * This type is syntactically identical to "multipart/mixed", but the semantics are different. In
    * particular, in a digest, the default {@code Content-Type} value for a body part is changed from
    * "text/plain" to "message/rfc822".
    */
-  public static final MediaType DIGEST = MediaType.parse("multipart/digest");
+  public static final MediaType DIGEST = MediaType.get("multipart/digest");
 
   /**
    * This type is syntactically identical to "multipart/mixed", but the semantics are different. In
    * particular, in a parallel entity, the order of body parts is not significant.
    */
-  public static final MediaType PARALLEL = MediaType.parse("multipart/parallel");
+  public static final MediaType PARALLEL = MediaType.get("multipart/parallel");
 
   /**
    * The media-type multipart/form-data follows the rules of all multipart MIME data streams as
    * outlined in RFC 2046. In forms, there are a series of fields to be supplied by the user who
    * fills out the form. Each field has a name. Within a given form, the names are unique.
    */
-  public static final MediaType FORM = MediaType.parse("multipart/form-data");
+  public static final MediaType FORM = MediaType.get("multipart/form-data");
 
   private static final byte[] COLONSPACE = {':', ' '};
   private static final byte[] CRLF = {'\r', '\n'};
@@ -74,7 +74,7 @@ public final class MultipartBody extends RequestBody {
   MultipartBody(ByteString boundary, MediaType type, List<Part> parts) {
     this.boundary = boundary;
     this.originalType = type;
-    this.contentType = MediaType.parse(type + "; boundary=" + boundary.utf8());
+    this.contentType = MediaType.get(type + "; boundary=" + boundary.utf8());
     this.parts = Util.immutableList(parts);
   }
 

samples/guide/src/main/java/okhttp3/guide/PostExample.java

@@ -8,8 +8,7 @@ import okhttp3.RequestBody;
 import okhttp3.Response;
 
 public class PostExample {
-  public static final MediaType JSON
+  public static final MediaType JSON = MediaType.get("application/json; charset=utf-8");
-      = MediaType.parse("application/json; charset=utf-8");
 
   OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/PostFile.java

@@ -25,7 +25,7 @@ import okhttp3.Response;
 
 public final class PostFile {
   public static final MediaType MEDIA_TYPE_MARKDOWN
-      = MediaType.parse("text/x-markdown; charset=utf-8");
+      = MediaType.get("text/x-markdown; charset=utf-8");
 
   private final OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/PostMultipart.java

@@ -30,7 +30,7 @@ public final class PostMultipart {
    * these examples, please request your own client ID! https://api.imgur.com/oauth2
    */
   private static final String IMGUR_CLIENT_ID = "9199fdef135c122";
-  private static final MediaType MEDIA_TYPE_PNG = MediaType.parse("image/png");
+  private static final MediaType MEDIA_TYPE_PNG = MediaType.get("image/png");
 
   private final OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/PostStreaming.java

@@ -25,7 +25,7 @@ import okio.BufferedSink;
 
 public final class PostStreaming {
   public static final MediaType MEDIA_TYPE_MARKDOWN
-      = MediaType.parse("text/x-markdown; charset=utf-8");
+      = MediaType.get("text/x-markdown; charset=utf-8");
 
   private final OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/PostStreamingWithPipe.java

@@ -27,7 +27,7 @@ import okio.Pipe;
 
 public final class PostStreamingWithPipe {
   public static final MediaType MEDIA_TYPE_MARKDOWN
-      = MediaType.parse("text/x-markdown; charset=utf-8");
+      = MediaType.get("text/x-markdown; charset=utf-8");
 
   private final OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/PostString.java

@@ -24,7 +24,7 @@ import okhttp3.Response;
 
 public final class PostString {
   public static final MediaType MEDIA_TYPE_MARKDOWN
-      = MediaType.parse("text/x-markdown; charset=utf-8");
+      = MediaType.get("text/x-markdown; charset=utf-8");
 
   private final OkHttpClient client = new OkHttpClient();
 

samples/guide/src/main/java/okhttp3/recipes/RequestBodyCompression.java

@@ -39,7 +39,7 @@ public final class RequestBodyCompression {
    * https://console.developers.google.com/project
    */
   public static final String GOOGLE_API_KEY = "AIzaSyAx2WZYe0My0i-uGurpvraYJxO7XNbwiGs";
-  public static final MediaType MEDIA_TYPE_JSON = MediaType.parse("application/json");
+  public static final MediaType MEDIA_TYPE_JSON = MediaType.get("application/json");
 
   private final OkHttpClient client = new OkHttpClient.Builder()
       .addInterceptor(new GzipRequestInterceptor())