我使用支持 Https 的服务从服务器获取数据。这里我使用自签名方法来创建httpClient。应用程序工作正常，但有时我会收到 IOExcetion 并且我的 api 调用失败。我无法从服务器获取数据。我为我的 httpClient 使用了 ConnectionTimeOut、SocketTimeouts。我不明白为什么我的 api 调用在某些情况下失败。在使用 https:// api 调用时如何避免 IOException？
这里我附上了自签名流程的代码。
SSLFactory 类：
public class MySSLSocketFactory extends SSLSocketFactory{
SSLContext sslContext = SSLContext.getInstance("TLS");
public MySSLSocketFactory(KeyStore truststore) throws NoSuchAlgorithmException,
KeyManagementException, KeyStoreException, UnrecoverableKeyException {
super(truststore);
TrustManager tm = new X509TrustManager() {
public java.security.cert.X509Certificate[] getAcceptedIssuers() {
return null;
}
@Override
public void checkClientTrusted(
java.security.cert.X509Certificate[] chain,
String authType)
throws java.security.cert.CertificateException {
}
@Override
public void checkServerTrusted(
java.security.cert.X509Certificate[] chain,
String authType)
throws java.security.cert.CertificateException {
}
};
sslContext.init(null, new TrustManager[] { tm }, null);
}
@Override
public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException {
return sslContext.getSocketFactory().createSocket(socket, host, port, autoClose);
}
@Override
public Socket createSocket() throws IOException {
return sslContext.getSocketFactory().createSocket();
}
}
我的 httpClient 对象方法如下：
public HttpClient getNewHttpClient(boolean containsTimeout) {
try {
KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf = new MySSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);
if(containsTimeout)
{
int timeout = 60000;
HttpConnectionParams.setConnectionTimeout(params, timeout);
HttpConnectionParams.setSoTimeout(params, timeout);
}
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
registry.register(new Scheme("https", sf, 8443));
ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);
return new DefaultHttpClient(ccm, params);
} catch (Exception e) {
return new DefaultHttpClient();
}
}
而我的api调用方法是
HttpClient httpclient = getNewHttpClient(true);
HttpPost httppost = new HttpPost(url);
httppost.setHeader("Content-Type", "text/xml");
BasicHttpResponse httpResponse = null;
httpResponse = (BasicHttpResponse) httpclient.execute(httppost);
InputStream is = httpResponse.getEntity().getContent();
上面的代码中（InputStream）是我的最终结果。
我在 10 次迭代中至少有 2 次没有得到最终结果。如何避免 IOException？
首先创建一个类名EasySSLSocketFactory
public class EasySSLSocketFactory implements SocketFactory,
LayeredSocketFactory {
private SSLContext sslcontext = null;
private static SSLContext createEasySSLContext() throws IOException {
try {
SSLContext context = SSLContext.getInstance("TLS");
context.init(null, new TrustManager[] { new EasyX509TrustManager(
null) }, null);
return context;
} catch (Exception e) {
throw new IOException(e.getMessage());
}
}
private SSLContext getSSLContext() throws IOException {
if (this.sslcontext == null) {
this.sslcontext = createEasySSLContext();
}
return this.sslcontext;
}
/**
* @see org.apache.http.conn.scheme.SocketFactory#connectSocket(java.net.Socket,
* java.lang.String, int, java.net.InetAddress, int,
* org.apache.http.params.HttpParams)
*/
public Socket connectSocket(Socket sock, String host, int port,
InetAddress localAddress, int localPort, HttpParams params)
throws IOException, UnknownHostException, ConnectTimeoutException {
int connTimeout = HttpConnectionParams.getConnectionTimeout(params);
int soTimeout = HttpConnectionParams.getSoTimeout(params);
InetSocketAddress remoteAddress = new InetSocketAddress(host, port);
SSLSocket sslsock = (SSLSocket) ((sock != null) ? sock : createSocket());
if ((localAddress != null) || (localPort > 0)) {
// we need to bind explicitly
if (localPort < 0) {
localPort = 0; // indicates "any"
}
InetSocketAddress isa = new InetSocketAddress(localAddress,
localPort);
sslsock.bind(isa);
}
sslsock.connect(remoteAddress, connTimeout);
sslsock.setSoTimeout(soTimeout);
return sslsock;
}
/**
* @see org.apache.http.conn.scheme.SocketFactory#createSocket()
*/
public Socket createSocket() throws IOException {
return getSSLContext().getSocketFactory().createSocket();
}
/**
* @see org.apache.http.conn.scheme.SocketFactory#isSecure(java.net.Socket)
*/
public boolean isSecure(Socket socket) throws IllegalArgumentException {
return true;
}
/**
* @see org.apache.http.conn.scheme.LayeredSocketFactory#createSocket(java.net.Socket,
* java.lang.String, int, boolean)
*/
public Socket createSocket(Socket socket, String host, int port,
boolean autoClose) throws IOException, UnknownHostException {
return getSSLContext().getSocketFactory().createSocket(socket, host,
port, autoClose);
}
// -------------------------------------------------------------------
// javadoc in org.apache.http.conn.scheme.SocketFactory says :
// Both Object.equals() and Object.hashCode() must be overridden
// for the correct operation of some connection managers
// -------------------------------------------------------------------
public boolean equals(Object obj) {
return ((obj != null) && obj.getClass().equals(
EasySSLSocketFactory.class));
}
public int hashCode() {
return EasySSLSocketFactory.class.hashCode();
}
}
然后实施X509信任管理器
public class EasyX509TrustManager implements X509TrustManager {
private X509TrustManager standardTrustManager = null;
/**
* Constructor for EasyX509TrustManager.
*/
public EasyX509TrustManager(KeyStore keystore)
throws NoSuchAlgorithmException, KeyStoreException {
super();
TrustManagerFactory factory = TrustManagerFactory
.getInstance(TrustManagerFactory.getDefaultAlgorithm());
factory.init(keystore);
TrustManager[] trustmanagers = factory.getTrustManagers();
if (trustmanagers.length == 0) {
throw new NoSuchAlgorithmException("no trust manager found");
}
this.standardTrustManager = (X509TrustManager) trustmanagers[0];
}
/**
* @see javax.net.ssl.X509TrustManager#checkClientTrusted(X509Certificate[],
* String authType)
*/
public void checkClientTrusted(X509Certificate[] certificates,
String authType) throws CertificateException {
standardTrustManager.checkClientTrusted(certificates, authType);
}
/**
* @see javax.net.ssl.X509TrustManager#checkServerTrusted(X509Certificate[],
* String authType)
*/
public void checkServerTrusted(X509Certificate[] certificates,
String authType) throws CertificateException {
if ((certificates != null) && (certificates.length == 1)) {
certificates[0].checkValidity();
} else {
standardTrustManager.checkServerTrusted(certificates, authType);
}
}
/**
* @see javax.net.ssl.X509TrustManager#getAcceptedIssuers()
*/
public X509Certificate[] getAcceptedIssuers() {
return this.standardTrustManager.getAcceptedIssuers();
}
}
现在您可以获取您的内容了
public class GetContent{
private ClientConnectionManager clientConnectionManager = null;
private HttpContext context = null;
private HttpParams params = null;
public GetContent() {
setup();
}
private HttpResponse getResponseFromUrl(String url) {
HttpResponse response = null;
try {
HttpConnectionParams.setConnectionTimeout(params, 300000);
HttpConnectionParams.setSoTimeout(params, 300000);
// connection (client has to be created for every new connection)
HttpClient client = new DefaultHttpClient(clientConnectionManager,
params);
HttpGet get = new HttpGet(url);
response = client.execute(get, context);
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return response;
}
public ClientConnectionManager getClientConnectionManager() {
return clientConnectionManager;
}
public HttpParams getHttpParams() {
return params;
}
public HttpContext getHttpContext() {
return context;
}
public InputStream getInputStream(final Context context, String url) {
InputStream is = null;
try {
HttpResponse response = getResponseFromUrl(url);
if (response != null) {
HttpEntity entity = response.getEntity();
if (entity != null)
is = entity.getContent();
return is;
}
} catch (ClientProtocolException e) {
Log.e("log_tag", "Error in http connection " + e.toString());
return null;
} catch (IOException e) {
e.printStackTrace();
return null;
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
return null;
}
return null;
}
private final void setup() {
SchemeRegistry schemeRegistry = new SchemeRegistry();
// http scheme
schemeRegistry.register(new Scheme("http", PlainSocketFactory
.getSocketFactory(), 80));
// https scheme
schemeRegistry.register(new Scheme("https", new EasySSLSocketFactory(),
443));
params = new BasicHttpParams();
params.setParameter(ConnManagerPNames.MAX_TOTAL_CONNECTIONS, 1);
params.setParameter(ConnManagerPNames.MAX_CONNECTIONS_PER_ROUTE,
new ConnPerRouteBean(1));
params.setParameter(HttpProtocolParams.USE_EXPECT_CONTINUE, false);
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, "utf8");
CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
// set the user credentials for our site "example.com"
credentialsProvider.setCredentials(new AuthScope("example.com",
AuthScope.ANY_PORT), new UsernamePasswordCredentials(
"UserNameHere", "UserPasswordHere"));
clientConnectionManager = new ThreadSafeClientConnManager(params,
schemeRegistry);
context = new BasicHttpContext();
context.setAttribute("http.auth.credentials-provider",
credentialsProvider);
}
}
这是如何获取InputStream
GetContent content =new GetContent();
InputStream is = content.getInputStream(this,MY_URL);
使用这样的东西
public void someMethod() throws IOException {
try {
// Do your work
} catch (MyException e){
throw new IOException(e.toString());
// or you can retry the same thing here without showing error
}
}
只需将代码放入 try catch 中即可
try {
HttpClient httpclient = getNewHttpClient(true);
HttpPost httppost = new HttpPost(url);
httppost.setHeader("Content-Type", "text/xml");
BasicHttpResponse httpResponse = null;
httpResponse = (BasicHttpResponse) httpclient.execute(httppost);
InputStream is = httpResponse.getEntity().getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}