Using supplier interface instead of custom interface, and renaming pr…

…operty

zookeeper-server/src/main/java/org/apache/zookeeper/common/X509Util.java

@@ -53,6 +53,7 @@
 import java.security.cert.X509CertSelector;
 import java.util.Arrays;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Supplier;
 
 /**
  * Utility code for X509 handling
@@ -104,7 +105,7 @@ public abstract class X509Util implements Closeable, AutoCloseable {
     private String sslTruststoreLocationProperty = getConfigPrefix() + "trustStore.location";
     private String sslTruststorePasswdProperty = getConfigPrefix() + "trustStore.password";
     private String sslTruststoreTypeProperty = getConfigPrefix() + "trustStore.type";
-    private String sslClientContextProperty = getConfigPrefix() + "client.context";
+    private String sslContextSupplierClassProperty = getConfigPrefix() + "context.supplier.class";
     private String sslHostnameVerificationEnabledProperty = getConfigPrefix() + "hostnameVerification";
     private String sslCrlEnabledProperty = getConfigPrefix() + "crl";
     private String sslOcspEnabledProperty = getConfigPrefix() + "ocsp";
@@ -160,8 +161,8 @@ public String getSslTruststoreTypeProperty() {
         return sslTruststoreTypeProperty;
     }
 
-    public String getSslClientContextProperty() {
-        return sslClientContextProperty;
+    public String getSslContextSupplierClassProperty() {
+        return sslContextSupplierClassProperty;
     }
 
     public String getSslHostnameVerificationEnabledProperty() {
@@ -238,18 +239,19 @@ public int getSslHandshakeTimeoutMillis() {
         return result;
     }
 
+    @SuppressWarnings("unchecked")
     public SSLContext createSSLContext(ZKConfig config) throws SSLContextException {
-        if (config.getProperty(sslClientContextProperty) != null) {
-            LOG.debug("Loading SSLContext from property '" + sslClientContextProperty + "'");
-            String sslClientContextClass = config.getProperty(sslClientContextProperty);
+        if (config.getProperty(sslContextSupplierClassProperty) != null) {
+            LOG.debug("Loading SSLContext supplier from property '" + sslContextSupplierClassProperty + "'");
+            String supplierContextClassName = config.getProperty(sslContextSupplierClassProperty);
             try {
-                Class<?> sslContextClass = Class.forName(sslClientContextClass);
-                ZKClientSSLContext sslContext = (ZKClientSSLContext) sslContextClass.getConstructor().newInstance();
-                return sslContext.getSSLContext();
+                Class<?> sslContextClass = Class.forName(supplierContextClassName);
+                Supplier<SSLContext> sslContextSupplier = (Supplier<SSLContext>) sslContextClass.getConstructor().newInstance();
+                return sslContextSupplier.get();
             } catch (ClassNotFoundException | ClassCastException | NoSuchMethodException | InvocationTargetException |
                     InstantiationException | IllegalAccessException e) {
-                throw new SSLContextException("Could not retrieve the SSLContext from source '" + sslClientContextClass +
-                        "' provided in the property '" + sslClientContextProperty + "'", e);
+                throw new SSLContextException("Could not retrieve the SSLContext from supplier source '" + supplierContextClassName +
+                        "' provided in the property '" + sslContextSupplierClassProperty + "'", e);
             }
         } else {
             return createSSLContextFromConfig(config);

zookeeper-server/src/main/java/org/apache/zookeeper/common/ZKConfig.java

@@ -18,6 +18,12 @@
 
 package org.apache.zookeeper.common;
 
+import org.apache.zookeeper.Environment;
+import org.apache.zookeeper.server.quorum.QuorumPeerConfig.ConfigException;
+import org.apache.zookeeper.server.util.VerifyingFileFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -26,12 +32,6 @@
 import java.util.Map.Entry;
 import java.util.Properties;
 
-import org.apache.zookeeper.Environment;
-import org.apache.zookeeper.server.quorum.QuorumPeerConfig.ConfigException;
-import org.apache.zookeeper.server.util.VerifyingFileFactory;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 /**
  * This class is a base class for the configurations of both client and server.
  * It supports reading client configuration from both system properties and
@@ -127,8 +127,8 @@ private void putSSLProperties(X509Util x509Util) {
                 System.getProperty(x509Util.getSslTruststorePasswdProperty()));
         properties.put(x509Util.getSslTruststoreTypeProperty(),
                 System.getProperty(x509Util.getSslTruststoreTypeProperty()));
-        properties.put(x509Util.getSslClientContextProperty(),
-                System.getProperty(x509Util.getSslClientContextProperty()));
+        properties.put(x509Util.getSslContextSupplierClassProperty(),
+                System.getProperty(x509Util.getSslContextSupplierClassProperty()));
         properties.put(x509Util.getSslHostnameVerificationEnabledProperty(),
                 System.getProperty(x509Util.getSslHostnameVerificationEnabledProperty()));
         properties.put(x509Util.getSslCrlEnabledProperty(),

zookeeper-server/src/test/java/org/apache/zookeeper/common/X509UtilTest.java

@@ -40,6 +40,7 @@
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
 import java.net.Socket;
+import java.security.NoSuchAlgorithmException;
 import java.security.Security;
 import java.util.Collection;
 import java.util.concurrent.Callable;
@@ -48,10 +49,10 @@
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Supplier;
 
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 @RunWith(Parameterized.class)
 public class X509UtilTest extends BaseX509ParameterizedTestCase {
@@ -406,26 +407,30 @@ public void testGetSslHandshakeDetectionTimeoutMillisProperty() {
         }
     }
 
+    @Test(expected = X509Exception.SSLContextException.class)
+    public void testCreateSSLContext_invalidCustomSSLContextClass() throws Exception {
+        ZKConfig zkConfig = new ZKConfig();
+        ClientX509Util clientX509Util = new ClientX509Util();
+        zkConfig.setProperty(clientX509Util.getSslContextSupplierClassProperty(), String.class.getCanonicalName());
+        clientX509Util.createSSLContext(zkConfig);
+    }
+
     @Test
-    public void testCreateSSLContext_invalidCustomSSLContextClass() {
+    public void testCreateSSLContext_validNullCustomSSLContextClass() throws X509Exception.SSLContextException {
         ZKConfig zkConfig = new ZKConfig();
         ClientX509Util clientX509Util = new ClientX509Util();
-        zkConfig.setProperty(clientX509Util.getSslClientContextProperty(), String.class.getCanonicalName());
-        try {
-            clientX509Util.createSSLContext(zkConfig);
-            fail("SSLContextException expected.");
-        } catch (X509Exception.SSLContextException e) {
-            assertTrue(e.getMessage().contains(clientX509Util.getSslClientContextProperty()));
-        }
+        zkConfig.setProperty(clientX509Util.getSslContextSupplierClassProperty(), X509UtilTest.class.getCanonicalName() + "$" + NullSslContextSupplier.class.getSimpleName());
+        final SSLContext sslContext = clientX509Util.createSSLContext(zkConfig);
+        assertNull(sslContext);
     }
 
     @Test
     public void testCreateSSLContext_validCustomSSLContextClass() throws X509Exception.SSLContextException {
         ZKConfig zkConfig = new ZKConfig();
         ClientX509Util clientX509Util = new ClientX509Util();
-        zkConfig.setProperty(clientX509Util.getSslClientContextProperty(), ZKTestClientSSLContext.class.getCanonicalName());
+        zkConfig.setProperty(clientX509Util.getSslContextSupplierClassProperty(), X509UtilTest.class.getCanonicalName() + "$" + SslContextSupplier.class.getSimpleName());
         final SSLContext sslContext = clientX509Util.createSSLContext(zkConfig);
-        assertNull(sslContext);
+        assertNotNull(sslContext);
     }
 
     private static void forceClose(Socket s) {
@@ -513,4 +518,27 @@ private void setCustomCipherSuites() {
         x509Util.close(); // remember to close old instance before replacing it
         x509Util = new ClientX509Util();
     }
+
+    public static class NullSslContextSupplier implements Supplier<SSLContext> {
+
+        @Override
+        public SSLContext get() {
+            return null;
+        }
+
+    }
+
+    public static class SslContextSupplier implements Supplier<SSLContext> {
+
+        @Override
+        public SSLContext get() {
+            try {
+                return SSLContext.getDefault();
+            } catch (NoSuchAlgorithmException e) {
+                return null;
+            }
+        }
+
+    }
+
 }