Dubbo源码之common模块URL

1.需求

         分析Dubbo中的URL

2.代码

public final class URL implements Serializable {

    private static final long serialVersionUID = -1985165475234910535L;

    private final String protocol;

    private final String username;

    private final String password;

    // by default, host to registry
    private final String host;

    // by default, port to registry
    private final int port;

    private final String path;

    private final Map<String, String> parameters;

.............
.............

  public static URL valueOf(String url) {
        if (url == null || (url = url.trim()).length() == 0) {
            throw new IllegalArgumentException("url == null");
        }
        String protocol = null;
        String username = null;
        String password = null;
        String host = null;
        int port = 0;
        String path = null;
        Map<String, String> parameters = null;
        int i = url.indexOf("?"); // seperator between body and parameters 
        if (i >= 0) {
            String[] parts = url.substring(i + 1).split("\\&");
            parameters = new HashMap<String, String>();
            for (String part : parts) {
                part = part.trim();
                if (part.length() > 0) {
                    int j = part.indexOf('=');
                    if (j >= 0) {
                        parameters.put(part.substring(0, j), part.substring(j + 1));
                    } else {
                        parameters.put(part, part);
                    }
                }
            }
            url = url.substring(0, i);
        }
        i = url.indexOf("://");
        if (i >= 0) {
            if (i == 0) throw new IllegalStateException("url missing protocol: \"" + url + "\"");
            protocol = url.substring(0, i);
            url = url.substring(i + 3);
        } else {
            // case: file:/path/to/file.txt
            i = url.indexOf(":/");
            if (i >= 0) {
                if (i == 0) throw new IllegalStateException("url missing protocol: \"" + url + "\"");
                protocol = url.substring(0, i);
                url = url.substring(i + 1);
            }
        }

        i = url.indexOf("/");
        if (i >= 0) {
            path = url.substring(i + 1);
            url = url.substring(0, i);
        }
        i = url.indexOf("@");
        if (i >= 0) {
            username = url.substring(0, i);
            int j = username.indexOf(":");
            if (j >= 0) {
                password = username.substring(j + 1);
                username = username.substring(0, j);
            }
            url = url.substring(i + 1);
        }
        i = url.indexOf(":");
        if (i >= 0 && i < url.length() - 1) {
            port = Integer.parseInt(url.substring(i + 1));
            url = url.substring(0, i);
        }
        if (url.length() > 0) host = url;
        return new URL(protocol, username, password, host, port, path, parameters);
    }


}

Dubbo中的URL形式

采用标准格式：protocol://username:password@host:port/path?key=value&key=value

举个栗子

例如：injvm://127.0.0.1/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&dubbo=2.0.0&generic=false&interface=com.alibaba.dubbo.demo.DemoService&loadbalance=roundrobin&methods=sayHello

Dubbo通过字符串切割获取URL信息

通过&和"="获取请求参数的保存为Map格式

通过"://"或者":/"获取请求的协议

通过"@"获取host等