io.netty.util.internal.EmptyArrays#EMPTY_STRINGS源码实例Demo

/**
 * Constructor specifying the destination web socket location
 *
 * @param version
 *            the protocol version
 * @param uri
 *            URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
 *            sent to this URL.
 * @param subprotocols
 *            CSV of supported protocols. Null if sub protocols not supported.
 * @param maxFramePayloadLength
 *            Maximum length of a frame's payload
 */
protected WebSocketServerHandshaker(
        WebSocketVersion version, String uri, String subprotocols,
        int maxFramePayloadLength) {
    this.version = version;
    this.uri = uri;
    if (subprotocols != null) {
        String[] subprotocolArray = subprotocols.split(",");
        for (int i = 0; i < subprotocolArray.length; i++) {
            subprotocolArray[i] = subprotocolArray[i].trim();
        }
        this.subprotocols = subprotocolArray;
    } else {
        this.subprotocols = EmptyArrays.EMPTY_STRINGS;
    }
    this.maxFramePayloadLength = maxFramePayloadLength;
}
 

@Override
public final String[] getEnabledCipherSuites() {
    final String[] enabled;
    synchronized (this) {
        if (!isDestroyed()) {
            enabled = SSL.getCiphers(ssl);
        } else {
            return EmptyArrays.EMPTY_STRINGS;
        }
    }
    if (enabled == null) {
        return EmptyArrays.EMPTY_STRINGS;
    } else {
        synchronized (this) {
            for (int i = 0; i < enabled.length; i++) {
                String mapped = toJavaCipherSuite(enabled[i]);
                if (mapped != null) {
                    enabled[i] = mapped;
                }
            }
        }
        return enabled;
    }
}
 

/**
 * Constructor specifying the destination web socket location
 *
 * @param version
 *            the protocol version
 * @param uri
 *            URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
 *            sent to this URL.
 * @param subprotocols
 *            CSV of supported protocols. Null if sub protocols not supported.
 * @param maxFramePayloadLength
 *            Maximum length of a frame's payload
 */
protected WebSocketServerHandshaker(
        WebSocketVersion version, String uri, String subprotocols,
        int maxFramePayloadLength) {
    this.version = version;
    this.uri = uri;
    if (subprotocols != null) {
        String[] subprotocolArray = StringUtil.split(subprotocols, ',');
        for (int i = 0; i < subprotocolArray.length; i++) {
            subprotocolArray[i] = subprotocolArray[i].trim();
        }
        this.subprotocols = subprotocolArray;
    } else {
        this.subprotocols = EmptyArrays.EMPTY_STRINGS;
    }
    this.maxFramePayloadLength = maxFramePayloadLength;
}
 

@Override
public String[] getValueNames() {
    Map<String, Object> values = this.values;
    if (values == null || values.isEmpty()) {
        return EmptyArrays.EMPTY_STRINGS;
    }
    return values.keySet().toArray(new String[values.size()]);
}
 

@Override
public String[] getEnabledCipherSuites() {
    String[] enabled = SSL.getCiphers(ssl);
    if (enabled == null) {
        return EmptyArrays.EMPTY_STRINGS;
    } else {
        for (int i = 0; i < enabled.length; i++) {
            String mapped = toJavaCipherSuite(enabled[i]);
            if (mapped != null) {
                enabled[i] = mapped;
            }
        }
        return enabled;
    }
}
 

@Override
public String[] getEnabledProtocols() {
    List<String> enabled = new ArrayList<String>();
    // Seems like there is no way to explict disable SSLv2Hello in openssl so it is always enabled
    enabled.add(PROTOCOL_SSL_V2_HELLO);
    int opts = SSL.getOptions(ssl);
    if ((opts & SSL.SSL_OP_NO_TLSv1) == 0) {
        enabled.add(PROTOCOL_TLS_V1);
    }
    if ((opts & SSL.SSL_OP_NO_TLSv1_1) == 0) {
        enabled.add(PROTOCOL_TLS_V1_1);
    }
    if ((opts & SSL.SSL_OP_NO_TLSv1_2) == 0) {
        enabled.add(PROTOCOL_TLS_V1_2);
    }
    if ((opts & SSL.SSL_OP_NO_SSLv2) == 0) {
        enabled.add(PROTOCOL_SSL_V2);
    }
    if ((opts & SSL.SSL_OP_NO_SSLv3) == 0) {
        enabled.add(PROTOCOL_SSL_V3);
    }
    int size = enabled.size();
    if (size == 0) {
        return EmptyArrays.EMPTY_STRINGS;
    } else {
        return enabled.toArray(new String[size]);
    }
}
 

@Override
public String[] getValueNames() {
    Map<String, Object> values = this.values;
    if (values == null || values.isEmpty()) {
        return EmptyArrays.EMPTY_STRINGS;
    }
    return values.keySet().toArray(new String[values.size()]);
}