Migrate NullSslSession to Java to fix deprecation warning

src/test/scala/tlschannel/helpers/NullSslSession.java

@@ -0,0 +1,116 @@
+package tlschannel.helpers;
+
+import java.security.Principal;
+import java.security.cert.Certificate;
+import javax.net.ssl.SSLSession;
+import javax.net.ssl.SSLSessionContext;
+import javax.security.cert.X509Certificate;
+
+public class NullSslSession implements SSLSession {
+
+    private final int bufferSize;
+
+    public NullSslSession(int bufferSize) {
+        this.bufferSize = bufferSize;
+    }
+
+    @Override
+    public byte[] getId() {
+        return new byte[0];
+    }
+
+    @Override
+    public SSLSessionContext getSessionContext() {
+        return null;
+    }
+
+    @Override
+    public long getCreationTime() {
+        return System.currentTimeMillis();
+    }
+
+    @Override
+    public long getLastAccessedTime() {
+        return System.currentTimeMillis();
+    }
+
+    @Override
+    public void invalidate() {}
+
+    @Override
+    public boolean isValid() {
+        return false;
+    }
+
+    @Override
+    public void putValue(String name, Object value) {}
+
+    @Override
+    public Object getValue(String name) {
+        return null;
+    }
+
+    @Override
+    public void removeValue(String name) {}
+
+    @Override
+    public String[] getValueNames() {
+        return new String[0];
+    }
+
+    @Override
+    public Certificate[] getPeerCertificates() {
+        return new Certificate[0];
+    }
+
+    @Override
+    public Certificate[] getLocalCertificates() {
+        return new Certificate[0];
+    }
+
+    @Override
+    public Principal getPeerPrincipal() {
+        return null;
+    }
+
+    @Override
+    public Principal getLocalPrincipal() {
+        return null;
+    }
+
+    @Override
+    public String getCipherSuite() {
+        return null;
+    }
+
+    @Override
+    public String getProtocol() {
+        return "";
+    }
+
+    @Override
+    public String getPeerHost() {
+        return null;
+    }
+
+    @Override
+    public int getPeerPort() {
+        return 0;
+    }
+
+    @Override
+    public int getPacketBufferSize() {
+        return 0;
+    }
+
+    @Override
+    public int getApplicationBufferSize() {
+        return bufferSize;
+    }
+
+    @Override
+    @SuppressWarnings("removal")
+    public X509Certificate[] getPeerCertificateChain() {
+        return new X509Certificate[0];
+    }
+}