Use check/require instead of if/throw

mockwebserver/src/main/java/okhttp3/mockwebserver/MockWebServer.kt

@@ -513,9 +513,7 @@ class MockWebServer : ExternalResource(), Closeable {
       val sink = raw.sink().buffer()
       while (true) {
         val socketPolicy = dispatcher.peek().getSocketPolicy()
-        if (!processOneRequest(raw, source, sink)) {
+        check(processOneRequest(raw, source, sink)) { "Tunnel without any CONNECT!" }
-          throw IllegalStateException("Tunnel without any CONNECT!")
-        }
         if (socketPolicy === UPGRADE_TO_SSL_AT_END) return
       }
     }
@@ -676,8 +674,8 @@ class MockWebServer : ExternalResource(), Closeable {
     }
 
     val method = request.substringBefore(' ')
-    if (hasBody && !HttpMethod.permitsRequestBody(method)) {
+    require(!hasBody || HttpMethod.permitsRequestBody(method)) {
-      throw IllegalArgumentException("Request must not have a body: $request")
+      "Request must not have a body: $request"
     }
 
     return RecordedRequest(request, headers.build(), chunkSizes, requestBody.receivedByteCount,

okhttp-dnsoverhttps/src/main/java/okhttp3/dnsoverhttps/DnsRecordCodec.kt

@@ -47,9 +47,7 @@ object DnsRecordCodec {
     val labels = host.split('.').dropLastWhile { it.isEmpty() }
     for (label in labels) {
       val utf8ByteCount = label.utf8Size()
-      if (utf8ByteCount != label.length.toLong()) {
+      require(utf8ByteCount == label.length.toLong()) { "non-ascii hostname: $host" }
-        throw IllegalArgumentException("non-ascii hostname: $host")
-      }
       nameBuf.writeByte(utf8ByteCount.toInt())
       nameBuf.writeUtf8(label)
     }
@@ -69,9 +67,7 @@ object DnsRecordCodec {
     buf.readShort() // query id
 
     val flags = buf.readShort().toInt() and 0xffff
-    if (flags shr 15 == 0) {
+    require(flags shr 15 != 0) { "not a response" }
-      throw IllegalArgumentException("not a response")
-    }
 
     val responseCode = flags and 0xf
 

okhttp/src/main/java/okhttp3/Cache.kt

@@ -352,7 +352,7 @@ class Cache internal constructor(
       }
 
       override fun remove() {
-        if (!canRemove) throw IllegalStateException("remove() before next()")
+        check(canRemove) { "remove() before next()" }
         delegate.remove()
       }
     }

okhttp/src/main/java/okhttp3/CacheControl.kt

@@ -193,7 +193,7 @@ class CacheControl private constructor(
      *     precision; finer precision will be lost.
      */
     fun maxAge(maxAge: Int, timeUnit: TimeUnit) = apply {
-      if (maxAge < 0) throw IllegalArgumentException("maxAge < 0: $maxAge")
+      require(maxAge >= 0) { "maxAge < 0: $maxAge" }
       val maxAgeSecondsLong = timeUnit.toSeconds(maxAge.toLong())
       this.maxAgeSeconds = maxAgeSecondsLong.clampToInt()
     }
@@ -206,7 +206,7 @@ class CacheControl private constructor(
      *     [TimeUnit.SECONDS] precision; finer precision will be lost.
      */
     fun maxStale(maxStale: Int, timeUnit: TimeUnit) = apply {
-      if (maxStale < 0) throw IllegalArgumentException("maxStale < 0: $maxStale")
+      require(maxStale >= 0) { "maxStale < 0: $maxStale" }
       val maxStaleSecondsLong = timeUnit.toSeconds(maxStale.toLong())
       this.maxStaleSeconds = maxStaleSecondsLong.clampToInt()
     }
@@ -220,7 +220,7 @@ class CacheControl private constructor(
      *     [TimeUnit.SECONDS] precision; finer precision will be lost.
      */
     fun minFresh(minFresh: Int, timeUnit: TimeUnit) = apply {
-      if (minFresh < 0) throw IllegalArgumentException("minFresh < 0: $minFresh")
+      require(minFresh >= 0) { "minFresh < 0: $minFresh" }
       val minFreshSecondsLong = timeUnit.toSeconds(minFresh.toLong())
       this.minFreshSeconds = minFreshSecondsLong.clampToInt()
     }

okhttp/src/main/java/okhttp3/HttpUrl.kt

@@ -877,7 +877,7 @@ class HttpUrl internal constructor(
     }
 
     fun port(port: Int): Builder {
-      if (port <= 0 || port > 65535) throw IllegalArgumentException("unexpected port: $port")
+      require(port in 1..65535) { "unexpected port: $port" }
       this.port = port
       return this
     }
@@ -926,8 +926,8 @@ class HttpUrl internal constructor(
 
     fun setPathSegment(index: Int, pathSegment: String): Builder {
       val canonicalPathSegment = pathSegment.canonicalize(encodeSet = PATH_SEGMENT_ENCODE_SET)
-      if (isDot(canonicalPathSegment) || isDotDot(canonicalPathSegment)) {
+      require(!isDot(canonicalPathSegment) && !isDotDot(canonicalPathSegment)) {
-        throw IllegalArgumentException("unexpected path segment: $pathSegment")
+        "unexpected path segment: $pathSegment"
       }
       encodedPathSegments[index] = canonicalPathSegment
       return this
@@ -939,8 +939,8 @@ class HttpUrl internal constructor(
           alreadyEncoded = true
       )
       encodedPathSegments[index] = canonicalPathSegment
-      if (isDot(canonicalPathSegment) || isDotDot(canonicalPathSegment)) {
+      require(!isDot(canonicalPathSegment) && !isDotDot(canonicalPathSegment)) {
-        throw IllegalArgumentException("unexpected path segment: $encodedPathSegment")
+        "unexpected path segment: $encodedPathSegment"
       }
       return this
     }
@@ -954,9 +954,7 @@ class HttpUrl internal constructor(
     }
 
     fun encodedPath(encodedPath: String): Builder {
-      if (!encodedPath.startsWith("/")) {
+      require(encodedPath.startsWith("/")) { "unexpected encodedPath: $encodedPath" }
-        throw IllegalArgumentException("unexpected encodedPath: $encodedPath")
-      }
       resolvePath(encodedPath, 0, encodedPath.length)
       return this
     }

okhttp/src/main/java/okhttp3/OkHttpClient.kt

@@ -17,16 +17,16 @@ package okhttp3
 
 import okhttp3.Protocol.HTTP_1_1
 import okhttp3.Protocol.HTTP_2
-import okhttp3.internal.checkDuration
 import okhttp3.internal.cache.InternalCache
+import okhttp3.internal.checkDuration
 import okhttp3.internal.eventListenerFactory
-import okhttp3.internal.toImmutableList
 import okhttp3.internal.immutableListOf
 import okhttp3.internal.platform.Platform
 import okhttp3.internal.platformTrustManager
 import okhttp3.internal.proxy.NullProxySelector
 import okhttp3.internal.tls.CertificateChainCleaner
 import okhttp3.internal.tls.OkHostnameVerifier
+import okhttp3.internal.toImmutableList
 import okhttp3.internal.ws.RealWebSocket
 import okio.Sink
 import okio.Source
@@ -531,9 +531,7 @@ open class OkHttpClient internal constructor(
      * If unset, the [system-wide default][SocketFactory.getDefault] socket factory will be used.
      */
     fun socketFactory(socketFactory: SocketFactory) = apply {
-      if (socketFactory is SSLSocketFactory) {
+      require(socketFactory !is SSLSocketFactory) { "socketFactory instanceof SSLSocketFactory" }
-        throw IllegalArgumentException("socketFactory instanceof SSLSocketFactory")
-      }
       this.socketFactory = socketFactory
     }
 

okhttp/src/main/java/okhttp3/internal/http/RealInterceptorChain.kt

@@ -77,10 +77,7 @@ class RealInterceptorChain(
 
   fun transmitter(): Transmitter = transmitter
 
-  fun exchange(): Exchange {
+  fun exchange(): Exchange = exchange!!
-    if (exchange == null) throw IllegalStateException()
-    return exchange
-  }
 
   override fun call(): Call = call
 
@@ -97,15 +94,13 @@ class RealInterceptorChain(
     calls++
 
     // If we already have a stream, confirm that the incoming request will use it.
-    if (this.exchange != null && !this.exchange.connection()!!.supportsUrl(request.url())) {
+    check(this.exchange == null || this.exchange.connection()!!.supportsUrl(request.url())) {
-      throw IllegalStateException("network interceptor " + interceptors[index - 1] +
+      "network interceptor ${interceptors[index - 1]} must retain the same host and port"
-          " must retain the same host and port")
     }
 
     // If we already have a stream, confirm that this is the only call to chain.proceed().
-    if (this.exchange != null && calls > 1) {
+    check(this.exchange == null || calls <= 1) {
-      throw IllegalStateException("network interceptor " + interceptors[index - 1] +
+      "network interceptor ${interceptors[index - 1]} must call proceed() exactly once"
-          " must call proceed() exactly once")
     }
 
     // Call the next interceptor in the chain.
@@ -118,15 +113,11 @@ class RealInterceptorChain(
         "interceptor $interceptor returned null")
 
     // Confirm that the next interceptor made its required call to chain.proceed().
-    if (exchange != null && index + 1 < interceptors.size && next.calls != 1) {
+    check(exchange == null || index + 1 >= interceptors.size || next.calls == 1) {
-      throw IllegalStateException("network interceptor " + interceptor +
+      "network interceptor $interceptor must call proceed() exactly once"
-          " must call proceed() exactly once")
     }
 
-    if (response.body() == null) {
+    check(response.body() != null) { "interceptor $interceptor returned a response with no body" }
-      throw IllegalStateException(
-          "interceptor $interceptor returned a response with no body")
-    }
 
     return response
   }

okhttp/src/main/java/okhttp3/internal/http1/Http1ExchangeCodec.kt

@@ -383,8 +383,8 @@ class Http1ExchangeCodec(
     }
 
     override fun read(sink: Buffer, byteCount: Long): Long {
-      if (byteCount < 0L) throw IllegalArgumentException("byteCount < 0: $byteCount")
+      require(byteCount >= 0L) { "byteCount < 0: $byteCount" }
-      if (closed) throw IllegalStateException("closed")
+      check(!closed) { "closed" }
       if (bytesRemaining == 0L) return -1
 
       val read = super.read(sink, minOf(bytesRemaining, byteCount))

okhttp/src/main/java/okhttp3/internal/platform/AndroidPlatform.kt

@@ -393,8 +393,7 @@ class AndroidPlatform(
         } catch (ignored: NoSuchMethodException) {
         }
       }
-      throw IllegalStateException(
+      throw IllegalStateException("Expected Android API level 21+ but was ${Build.VERSION.SDK_INT}")
-          "Expected Android API level 21+ but was " + Build.VERSION.SDK_INT)
     }
   }
 }

okhttp/src/main/java/okhttp3/internal/ws/WebSocketProtocol.kt

@@ -131,9 +131,7 @@ object WebSocketProtocol {
 
   fun validateCloseCode(code: Int) {
     val message = closeCodeExceptionMessage(code)
-    if (message != null) {
+    require(message == null) { message!! }
-      throw IllegalArgumentException(message)
-    }
   }
 
   fun acceptHeader(key: String): String {