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package com.sun.net.httpserver.spi;

import com.sun.net.httpserver.HttpServer;
import com.sun.net.httpserver.HttpsServer;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Iterator;
import java.util.ServiceConfigurationError;
import java.util.ServiceLoader;

Service provider class for HttpServer. Sub-classes of HttpServerProvider provide an implementation of HttpServer and associated classes. Applications do not normally use this class. See provider() for how providers are found and loaded.
/** * Service provider class for HttpServer. * Sub-classes of HttpServerProvider provide an implementation of * {@link HttpServer} and associated classes. Applications do not normally use * this class. See {@link #provider()} for how providers are found and loaded. */
public abstract class HttpServerProvider {
creates a HttpServer from this provider
Params:
  • addr – the address to bind to. May be null
  • backlog – the socket backlog. A value of zero means the systems default
Throws:
Returns:An instance of HttpServer
/** * creates a HttpServer from this provider * * @param addr * the address to bind to. May be {@code null} * * @param backlog * the socket backlog. A value of {@code zero} means the systems default * @throws IOException if an I/O error occurs * @return An instance of HttpServer */
public abstract HttpServer createHttpServer(InetSocketAddress addr, int backlog) throws IOException;
creates a HttpsServer from this provider
Params:
  • addr – the address to bind to. May be null
  • backlog – the socket backlog. A value of zero means the systems default
Throws:
Returns:An instance of HttpServer
/** * creates a HttpsServer from this provider * * @param addr * the address to bind to. May be {@code null} * * @param backlog * the socket backlog. A value of {@code zero} means the systems default * @throws IOException if an I/O error occurs * @return An instance of HttpServer */
public abstract HttpsServer createHttpsServer(InetSocketAddress addr, int backlog) throws IOException; private static final Object lock = new Object(); private static HttpServerProvider provider = null;
Initializes a new instance of this class.
Throws:
  • SecurityException – If a security manager has been installed and it denies RuntimePermission("httpServerProvider")
/** * Initializes a new instance of this class. * * @throws SecurityException * If a security manager has been installed and it denies * {@link RuntimePermission}{@code ("httpServerProvider")} */
protected HttpServerProvider() { SecurityManager sm = System.getSecurityManager(); if (sm != null) sm.checkPermission(new RuntimePermission("httpServerProvider")); } private static boolean loadProviderFromProperty() { String cn = System.getProperty("com.sun.net.httpserver.HttpServerProvider"); if (cn == null) return false; try { @SuppressWarnings("deprecation") Object o = Class.forName(cn, true, ClassLoader.getSystemClassLoader()).newInstance(); provider = (HttpServerProvider)o; return true; } catch (ClassNotFoundException | IllegalAccessException | InstantiationException | SecurityException x) { throw new ServiceConfigurationError(null, x); } } private static boolean loadProviderAsService() { Iterator<HttpServerProvider> i = ServiceLoader.load(HttpServerProvider.class, ClassLoader.getSystemClassLoader()) .iterator(); for (;;) { try { if (!i.hasNext()) return false; provider = i.next(); return true; } catch (ServiceConfigurationError sce) { if (sce.getCause() instanceof SecurityException) { // Ignore the security exception, try the next provider continue; } throw sce; } } }
Returns the system wide default HttpServerProvider for this invocation of the Java virtual machine.

The first invocation of this method locates the default provider object as follows:

  1. If the system property com.sun.net.httpserver.HttpServerProvider is defined then it is taken to be the fully-qualified name of a concrete provider class. The class is loaded and instantiated; if this process fails then an unspecified unchecked error or exception is thrown.

  2. If a provider class has been installed in a jar file that is visible to the system class loader, and that jar file contains a provider-configuration file named com.sun.net.httpserver.HttpServerProvider in the resource directory META-INF/services, then the first class name specified in that file is taken. The class is loaded and instantiated; if this process fails then an unspecified unchecked error or exception is thrown.

  3. Finally, if no provider has been specified by any of the above means then the system-default provider class is instantiated and the result is returned.

Subsequent invocations of this method return the provider that was returned by the first invocation.

Returns: The system-wide default HttpServerProvider
/** * Returns the system wide default HttpServerProvider for this invocation of * the Java virtual machine. * * <p> The first invocation of this method locates the default provider * object as follows: </p> * * <ol> * * <li><p> If the system property * {@systemProperty com.sun.net.httpserver.HttpServerProvider} * is defined then it is taken to be the fully-qualified name * of a concrete provider class. * The class is loaded and instantiated; if this process fails then an * unspecified unchecked error or exception is thrown. </p></li> * * <li><p> If a provider class has been installed in a jar file that is * visible to the system class loader, and that jar file contains a * provider-configuration file named * {@code com.sun.net.httpserver.HttpServerProvider} in the resource * directory {@code META-INF/services}, then the first class name * specified in that file is taken. The class is loaded and * instantiated; if this process fails then an unspecified unchecked error * or exception is thrown. </p></li> * * <li><p> Finally, if no provider has been specified by any of the above * means then the system-default provider class is instantiated and the * result is returned. </p></li> * * </ol> * * <p> Subsequent invocations of this method return the provider that was * returned by the first invocation. </p> * * @return The system-wide default HttpServerProvider */
public static HttpServerProvider provider () { synchronized (lock) { if (provider != null) return provider; return (HttpServerProvider)AccessController .doPrivileged(new PrivilegedAction<Object>() { public Object run() { if (loadProviderFromProperty()) return provider; if (loadProviderAsService()) return provider; provider = new sun.net.httpserver.DefaultHttpServerProvider(); return provider; } }); } } }