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CookieManager setCookie Expires字

2019-05-16  本文已影响9人  Android架构
CookieManager cookieManager = CookieManager.getInstance();
String domain = ".bilibili.com";
String cookie1 = "bili_jct=b33fd713ea7cc6d29d65462794b28441; Domain=.bilibili.com; Expires=Expires=Sun, 18 Jan 1970 22:11:45 GMT+08:00";
String cookie2 = "bili_jct=49b9bcc2c21f19cc9dcb8382b84cf552; Domain=.bilibili.com; Expires=Expires=周日, 18 1月 1970 22:11:40 GMT+08:00";
cookieManager.setCookie(domain, cookie1);
String cookie1R = cookieManager.getCookie(domain);
Log.i("Cookie","load cookie1 "+cookie1R);
cookieManager.setCookie(domain, cookie2);
String cookie2R = cookieManager.getCookie(domain);
Log.i("Cookie","load cookie1 "+cookie2R);

输出

: load cookie1 null
: load cookie1 bili_jct=49b9bcc2c21f19cc9dcb8382b84cf552

问题原因就是英文状态是会识别Expires,所以在存入cookie1后CookieManager会认为这个cookie是过期的,所以会忽略掉这个cookie,返回null,但是在中文是不会识别Expires,所以可以返回cookie.
我尝试去跟踪了一下源码去发现为什么会出现这种情况

public abstract class CookieManager{
       public abstract void setCookie(String url, String value);
}

CookieManager是一个抽象类,setCookie也是一个抽象方法,所以必需找到其实现类

public static CookieManager getInstance() {
        return WebViewFactory.getProvider().getCookieManager();
}

进入getProvider

static WebViewFactoryProvider getProvider() {
        synchronized (sProviderLock) {
            // For now the main purpose of this function (and the factory abstraction) is to keep
            // us honest and minimize usage of WebView internals when binding the proxy.
            if (sProviderInstance != null) return sProviderInstance;
            //代码省略
            try {
                Class<WebViewFactoryProvider> providerClass = getProviderClass();
                Method staticFactory = null;
                try {
                    staticFactory = providerClass.getMethod(
                        CHROMIUM_WEBVIEW_FACTORY_METHOD, WebViewDelegate.class);
                } catch (Exception e) {
                    if (DEBUG) {
                        Log.w(LOGTAG, "error instantiating provider with static factory method", e);
                    }
                }

                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactoryProvider invocation");
                try {
                    sProviderInstance = (WebViewFactoryProvider)
                            staticFactory.invoke(null, new WebViewDelegate());
                    if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance);
                    return sProviderInstance;
                } catch (Exception e) {
                    Log.e(LOGTAG, "error instantiating provider", e);
                    throw new AndroidRuntimeException(e);
                } finally {
                    Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
                }
            } finally {
                Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
                StrictMode.setThreadPolicy(oldPolicy);
            }
        }
    }

可以看到sProviderInstance就是我们要的WebViewFactoryProvider,WebViewFactoryProvider是一个接口,它的创建实际上分为两步。

第一步:获取工厂类,这个工厂是用来创建WebViewFactoryProvider的实现类.

 Class<WebViewFactoryProvider> providerClass = getProviderClass();
private static Class<WebViewFactoryProvider> getProviderClass() {
        //代码省略
       ClassLoader clazzLoader = webViewContext.getClassLoader();
       return getWebViewProviderClass(clazzLoader);
}
public static Class<WebViewFactoryProvider> getWebViewProviderClass(ClassLoader clazzLoader)
            throws ClassNotFoundException {
        return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY,
                true, clazzLoader);
    }
private static final String CHROMIUM_WEBVIEW_FACTORY =
            "com.android.webview.chromium.WebViewChromiumFactoryProviderForO";

WebViewChromiumFactoryProviderForO就是目前获取的工厂类.

第二步:通过WebViewFactoryProvider的工厂类(现在已经知道了是WebViewChromiumFactoryProviderForO)创建WebViewFactoryProvider的实现类

再回到getProvider中看看下面这些代码:

                Method staticFactory = null;
                try {
                    staticFactory = providerClass.getMethod(
                        CHROMIUM_WEBVIEW_FACTORY_METHOD, WebViewDelegate.class);
                } catch (Exception e) {
                    if (DEBUG) {
                        Log.w(LOGTAG, "error instantiating provider with static factory method", e);
                    }
                }

                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactoryProvider invocation");
                try {
                    sProviderInstance = (WebViewFactoryProvider)
                            staticFactory.invoke(null, new WebViewDelegate());

可以看出来它是通过反射WebViewChromiumFactoryProviderForO的CHROMIUM_WEBVIEW_FACTORY_METHOD方法获取WebViewFactoryProvider的实现类.

private static final String CHROMIUM_WEBVIEW_FACTORY_METHOD = "create";

源码中的CHROMIUM_WEBVIEW_FACTORY_METHOD是一个create函数.
Ok,我们现在找到了WebViewFactoryProvider的实现类是通过高反射WebViewChromiumFactoryProviderForO调用create创建的,那下面来看看WebViewChromiumFactoryProviderForO的源码怎么实现create.

class WebViewChromiumFactoryProviderForO extends WebViewChromiumFactoryProvider {
    public static WebViewChromiumFactoryProvider create(android.webkit.WebViewDelegate delegate) {
        return new WebViewChromiumFactoryProviderForO(delegate);
    }

    protected WebViewChromiumFactoryProviderForO(android.webkit.WebViewDelegate delegate) {
        super(delegate);
    }
}

可以看出来WebViewChromiumFactoryProviderForO的create方法创建的其实就是它自己,但是它的很多方法都是在父类里面的,我们需要跟进父类去看看getCookieManager到底返回的是什么,才能知道CookieManager的实现类是什么.
···
public class WebViewChromiumFactoryProvider implements WebViewFactoryProvider {
@Override
public CookieManager getCookieManager() {
synchronized (mLock) {
if (mCookieManager == null) {
if (!mStarted) {
// We can use CookieManager without starting Chromium; the native code
// will bring up just the parts it needs to make this work on a temporary
// basis until Chromium is started for real. The temporary cookie manager
// needs the application context to have been set.
ContentMain.initApplicationContext(mWebViewDelegate.getApplication());
}
mCookieManager = new CookieManagerAdapter(new AwCookieManager());
}
}
return mCookieManager;
}
}
···
WebViewChromiumFactoryProvider中的getCookieManager返回的是一个CookieManagerAdapter,这里终于找到了CookieManager的实现类是CookieManagerAdapter
继续看看CookieManagerAdapter的setCookie函数怎么实现的

public class CookieManagerAdapter extends CookieManager {

AwCookieManager mChromeCookieManager;

@Override
    public void setCookie(String url, String value) {
        try {
            mChromeCookieManager.setCookie(fixupUrl(url), value);
        } catch (ParseException e) {
            Log.e(LOGTAG, "Not setting cookie due to error parsing URL: " + url, e);
        }
    }
}
@JNINamespace("android_webview")
public final class AwCookieManager {
    /**
     * Set cookie for a given url. The old cookie with same host/path/name will
     * be removed. The new cookie will be added if it is not expired or it does
     * not have expiration which implies it is session cookie.
     * @param url The url which cookie is set for
     * @param value The value for set-cookie: in http response header
     */
   public void setCookie(final String url, final String value) {
        nativeSetCookie(url, value);
    }
   private native void nativeSetCookie(String url, String value);
}

最终走到了一个nativeSetCookie方法,它是native方法. so,目前暂时也没有办法跟进了,目前只能从注释推断这其实中文情况下面expiration是无效的.

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