A subroute on a client must match a subroute on the server. So routes cannot be used for dynamic routing, unlike HTTP.

Handlers should remain backwards compatible. If a breaking API change is required, a new handler ID should be created.

## Setup & Configuration

A **Manager** is used to manage all incoming and outgoing connections to a server.

On startup all remote servers must be specified.

		{"TEXT", "", "expect two or three operands for TEXT"},
		{"TEXT", "%", "expect two or three operands for TEXT"},
		{"TEXT", "1, 1", "TEXT symbol \"<erroneous symbol>\" must be a symbol(SB)"},
		{"TEXT", "$\"foo\", 0, $1", "TEXT symbol \"<erroneous symbol>\" must be a symbol(SB)"},
		{"TEXT", "$0É:0, 0, $1", "expected end of operand, found É"}, // Issue #12467.
		{"TEXT", "$:0:(SB, 0, $1", "expected '(', found 0"},          // Issue 12468.

				prog.To = a[2]
				break
			}
			if arch.IsARMBFX(op) {
				// a[0] and a[1] must be constants, a[2] must be a register
				prog.From = a[0]
				prog.AddRestSource(a[1])
				prog.To = a[2]
				break
			}
			// Otherwise the 2nd operand (a[1]) must be a register.
			prog.From = a[0]
			prog.Reg = p.getRegister(prog, op, &a[1])
			prog.To = a[2]
		case sys.AMD64:

     *
     * @param settings The settings to validate, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */
    void validate(Settings settings, SettingsProblemCollector problems);

    /**
     * Validate the specified settings.
     *
     * @param settings The settings to validate, must not be {@code null}.

      assertThat(expected.message).isEqualTo(
        "Payload size must be less than or equal to 125",
      )
    }
  }

  @Test fun pongTooLongThrows() {
    assertFailsWith<IllegalArgumentException> {
      serverWriter.writePong((binaryData(1000)))
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "Payload size must be less than or equal to 125",
      )
    }
  }

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * The annotated element must not be null.
 * <p>
 * Annotated fields must not be null after construction has completed.
 * <p>
 * When this annotation is applied to a method it applies to the method return value.
 *
 * @see Nullable
 * @since 4.0.0
 */
@Experimental

    // https://daniel.haxx.se/blog/2016/08/18/http2-connection-coalescing/

    // 1. This connection must be HTTP/2.
    if (http2Connection == null) return false

    // 2. The routes must share an IP address.
    if (routes == null || !routeMatchesAny(routes)) return false

    // 3. This connection's server certificates must cover the new host.
    if (address.hostnameVerifier !== OkHostnameVerifier) return false

   *
   * <ul>
   *   <li>Both {@code xStats} and {@code yStats} must have the same {@code count}.
   *   <li>If that {@code count} is 1, {@code sumOfProductsOfDeltas} must be exactly 0.0.
   *   <li>If that {@code count} is more than 1, {@code sumOfProductsOfDeltas} must be finite.
   * </ul>
   */
  PairedStats(Stats xStats, Stats yStats, double sumOfProductsOfDeltas) {

    }

    /**
     * Adds {@code node} if it is not already present.
     *
     * <p><b>Nodes must be unique</b>, just as {@code Map} keys must be. They must also be non-null.
     *
     * @return this {@code Builder} object
     */
    @CanIgnoreReturnValue
    public Builder<N> addNode(N node) {
      mutableGraph.addNode(node);

 * interceptors, the OkHttp core, all network interceptors, and finally the network caller.
 *
 * If the chain is for an application interceptor then [exchange] must be null. Otherwise it is for
 * a network interceptor and [exchange] must be non-null.
 */
class RealInterceptorChain(
  internal val call: RealCall,
  private val interceptors: List<Interceptor>,
  private val index: Int,