Java tutorial
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For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http2.impl.client; import java.util.Arrays; import java.util.Collections; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Queue; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.http2.FormattedHeader; import org.apache.http2.Header; import org.apache.http2.HttpHost; import org.apache.http2.HttpResponse; import org.apache.http2.annotation.Immutable; import org.apache.http2.auth.AuthOption; import org.apache.http2.auth.AuthScheme; import org.apache.http2.auth.AuthSchemeRegistry; import org.apache.http2.auth.AuthScope; import org.apache.http2.auth.Credentials; import org.apache.http2.auth.MalformedChallengeException; import org.apache.http2.client.AuthCache; import org.apache.http2.client.AuthenticationStrategy; import org.apache.http2.client.CredentialsProvider; import org.apache.http2.client.params.AuthPolicy; import org.apache.http2.client.protocol.ClientContext; import org.apache.http2.protocol.HTTP; import org.apache.http2.protocol.HttpContext; import org.apache.http2.util.CharArrayBuffer; @Immutable class AuthenticationStrategyImpl implements AuthenticationStrategy { private final Log log = LogFactory.getLog(getClass()); private static final List<String> DEFAULT_SCHEME_PRIORITY = Collections .unmodifiableList(Arrays.asList(new String[] { AuthPolicy.SPNEGO, AuthPolicy.KERBEROS, AuthPolicy.NTLM, AuthPolicy.DIGEST, AuthPolicy.BASIC })); private final int challengeCode; private final String headerName; private final String prefParamName; AuthenticationStrategyImpl(int challengeCode, final String headerName, final String prefParamName) { super(); this.challengeCode = challengeCode; this.headerName = headerName; this.prefParamName = prefParamName; } public boolean isAuthenticationRequested(final HttpHost authhost, final HttpResponse response, final HttpContext context) { if (response == null) { throw new IllegalArgumentException("HTTP response may not be null"); } int status = response.getStatusLine().getStatusCode(); return status == this.challengeCode; } public Map<String, Header> getChallenges(final HttpHost authhost, final HttpResponse response, final HttpContext context) throws MalformedChallengeException { if (response == null) { throw new IllegalArgumentException("HTTP response may not be null"); } Header[] headers = response.getHeaders(this.headerName); Map<String, Header> map = new HashMap<String, Header>(headers.length); for (Header header : headers) { CharArrayBuffer buffer; int pos; if (header instanceof FormattedHeader) { buffer = ((FormattedHeader) header).getBuffer(); pos = ((FormattedHeader) header).getValuePos(); } else { String s = header.getValue(); if (s == null) { throw new MalformedChallengeException("Header value is null"); } buffer = new CharArrayBuffer(s.length()); buffer.append(s); pos = 0; } while (pos < buffer.length() && HTTP.isWhitespace(buffer.charAt(pos))) { pos++; } int beginIndex = pos; while (pos < buffer.length() && !HTTP.isWhitespace(buffer.charAt(pos))) { pos++; } int endIndex = pos; String s = buffer.substring(beginIndex, endIndex); map.put(s.toLowerCase(Locale.US), header); } return map; } public Queue<AuthOption> select(final Map<String, Header> challenges, final HttpHost authhost, final HttpResponse response, final HttpContext context) throws MalformedChallengeException { if (challenges == null) { throw new IllegalArgumentException("Map of auth challenges may not be null"); } if (authhost == null) { throw new IllegalArgumentException("Host may not be null"); } if (response == null) { throw new IllegalArgumentException("HTTP response may not be null"); } if (context == null) { throw new IllegalArgumentException("HTTP context may not be null"); } Queue<AuthOption> options = new LinkedList<AuthOption>(); AuthSchemeRegistry registry = (AuthSchemeRegistry) context.getAttribute(ClientContext.AUTHSCHEME_REGISTRY); if (registry == null) { this.log.debug("Auth scheme registry not set in the context"); return options; } CredentialsProvider credsProvider = (CredentialsProvider) context .getAttribute(ClientContext.CREDS_PROVIDER); if (credsProvider == null) { this.log.debug("Credentials provider not set in the context"); return options; } @SuppressWarnings("unchecked") List<String> authPrefs = (List<String>) response.getParams().getParameter(this.prefParamName); if (authPrefs == null) { authPrefs = DEFAULT_SCHEME_PRIORITY; } if (this.log.isDebugEnabled()) { this.log.debug("Authentication schemes in the order of preference: " + authPrefs); } for (String id : authPrefs) { Header challenge = challenges.get(id.toLowerCase(Locale.US)); if (challenge != null) { try { AuthScheme authScheme = registry.getAuthScheme(id, response.getParams()); authScheme.processChallenge(challenge); AuthScope authScope = new AuthScope(authhost.getHostName(), authhost.getPort(), authScheme.getRealm(), authScheme.getSchemeName()); Credentials credentials = credsProvider.getCredentials(authScope); if (credentials != null) { options.add(new AuthOption(authScheme, credentials)); } } catch (IllegalStateException e) { if (this.log.isWarnEnabled()) { this.log.warn("Authentication scheme " + id + " not supported"); // Try again } } } else { if (this.log.isDebugEnabled()) { this.log.debug("Challenge for " + id + " authentication scheme not available"); // Try again } } } return options; } public void authSucceeded(final HttpHost authhost, final AuthScheme authScheme, final HttpContext context) { if (authhost == null) { throw new IllegalArgumentException("Host may not be null"); } if (authScheme == null) { throw new IllegalArgumentException("Auth scheme may not be null"); } if (context == null) { throw new IllegalArgumentException("HTTP context may not be null"); } if (isCachable(authScheme)) { AuthCache authCache = (AuthCache) context.getAttribute(ClientContext.AUTH_CACHE); if (authCache == null) { authCache = new BasicAuthCache(); context.setAttribute(ClientContext.AUTH_CACHE, authCache); } if (this.log.isDebugEnabled()) { this.log.debug("Caching '" + authScheme.getSchemeName() + "' auth scheme for " + authhost); } authCache.put(authhost, authScheme); } } protected boolean isCachable(final AuthScheme authScheme) { if (authScheme == null || !authScheme.isComplete()) { return false; } String schemeName = authScheme.getSchemeName(); return schemeName.equalsIgnoreCase(AuthPolicy.BASIC) || schemeName.equalsIgnoreCase(AuthPolicy.DIGEST); } public void authFailed(final HttpHost authhost, final AuthScheme authScheme, final HttpContext context) { if (authhost == null) { throw new IllegalArgumentException("Host may not be null"); } if (context == null) { throw new IllegalArgumentException("HTTP context may not be null"); } AuthCache authCache = (AuthCache) context.getAttribute(ClientContext.AUTH_CACHE); if (authCache != null) { if (this.log.isDebugEnabled()) { this.log.debug("Clearing cached auth scheme for " + authhost); } authCache.remove(authhost); } } }