@Reference
private DoSomeThingService doSomeThingService;

public String sayHello() {
    RpcContext.getContext().setAttachment(CommonConstants.TAG_KEY, "tag1");
    return doSomeThingService.sayHello();
}

public String sayHello() {
    RpcContext.getContext().setAttachment(CommonConstants.TAG_KEY, "tag1");
    return doSomeThingService.sayHello();
}

@Override
public synchronized void process(ConfigChangedEvent event) {
    if (logger.isDebugEnabled()) {
        logger.debug("Notification of tag rule, change type is: " + event.getChangeType() + ", raw rule is:\n " +
                event.getContent());
    }

    try {
        if (event.getChangeType().equals(ConfigChangeType.DELETED)) {
            this.tagRouterRule = null;
        } else {
            this.tagRouterRule = TagRuleParser.parse(event.getContent());
        }
    } catch (Exception e) {
        logger.error("Failed to parse the raw tag router rule and it will not take effect, please check if the " +
                "rule matches with the template, the raw rule is:\n ", e);
    }
}

// Create the tabs that make up the user interface.
mTabLayout = (TabLayout) findViewById(R.id.tabs);
final int tabCount = UiDataModel.getUiDataModel().getTabCount();
final boolean showTabLabel = getResources().getBoolean(R.bool.showTabLabel);
final boolean showTabHorizontally = getResources().getBoolean(R.bool.showTabHorizontally);
for (int i = 0; i < tabCount; i++) {
    final UiDataModel.Tab tabModel = UiDataModel.getUiDataModel().getTab(i);
    final @StringRes int labelResId = tabModel.getLabelResId();

    final TabLayout.Tab tab = mTabLayout.newTab()
            .setTag(tabModel)
            .setIcon(tabModel.getIconResId())
            .setContentDescription(labelResId);

    if (showTabLabel) {
        tab.setText(labelResId);
        tab.setCustomView(R.layout.tab_item);

        @SuppressWarnings("ConstantConditions")
        final TextView text = (TextView) tab.getCustomView()
                .findViewById(android.R.id.text1);
        text.setTextColor(mTabLayout.getTabTextColors());

        // Bind the icon to the TextView.
        final Drawable icon = tab.getIcon();
        if (showTabHorizontally) {
            // Remove the icon so it doesn't affect the minimum TabLayout height.
            tab.setIcon(null);
            text.setCompoundDrawablesRelativeWithIntrinsicBounds(icon, null, null, null);
        } else {
            text.setCompoundDrawablesRelativeWithIntrinsicBounds(null, icon, null, null);
        }
    }

/** Identifies each of the primary tabs within the application. */
public enum Tab {
    ALARMS(AlarmClockFragment.class, R.drawable.ic_tab_alarm, R.string.menu_alarm),
    CLOCKS(ClockFragment.class, R.drawable.ic_tab_clock, R.string.menu_clock),
    TIMERS(TimerFragment.class, R.drawable.ic_tab_timer, R.string.menu_timer),
    STOPWATCH(StopwatchFragment.class, R.drawable.ic_tab_stopwatch, R.string.menu_stopwatch);

    private final String mFragmentClassName;
    private final @DrawableRes int mIconResId;
    private final @StringRes int mLabelResId;

    Tab(Class fragmentClass, @DrawableRes int iconResId, @StringRes int labelResId) {
        mFragmentClassName = fragmentClass.getName();
        mIconResId = iconResId;
        mLabelResId = labelResId;
    }

    public String getFragmentClassName() { return mFragmentClassName; }
    public @DrawableRes int getIconResId() { return mIconResId; }
    public @StringRes int getLabelResId() { return mLabelResId; }
}

// Customize the view pager.
mFragmentTabPagerAdapter = new FragmentTabPagerAdapter(this);
mFragmentTabPager = (ViewPager) findViewById(R.id.desk_clock_pager);
// Keep all four tabs to minimize jank.
mFragmentTabPager.setOffscreenPageLimit(3);
// Set Accessibility Delegate to null so view pager doesn't intercept movements and
// prevent the fab from being selected.
mFragmentTabPager.setAccessibilityDelegate(null);
// Mirror changes made to the selected page of the view pager into UiDataModel.
mFragmentTabPager.addOnPageChangeListener(new PageChangeWatcher());
mFragmentTabPager.setAdapter(mFragmentTabPagerAdapter);

// Mirror changes made to the selected tab into UiDataModel.
mTabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
    @Override
    public void onTabSelected(TabLayout.Tab tab) {
        UiDataModel.getUiDataModel().setSelectedTab((UiDataModel.Tab) tab.getTag());
    }

    @Override
    public void onTabUnselected(TabLayout.Tab tab) {
    }

    @Override
    public void onTabReselected(TabLayout.Tab tab) {
    }
});

/**
 * This adapter produces the DeskClockFragments that are the content of the DeskClock tabs. The
 * adapter presents the tabs in LTR and RTL order depending on the text layout direction for the
 * current locale. To prevent issues when switching between LTR and RTL, fragments are registered
 * with the manager using position-independent tags, which is an important departure from
 * FragmentPagerAdapter.
 */
final class FragmentTabPagerAdapter extends PagerAdapter {

    private final DeskClock mDeskClock;

    /** The manager into which fragments are added. */
    private final FragmentManager mFragmentManager;

    /** A fragment cache that can be accessed before {@link #instantiateItem} is called. */
    private final Map<UiDataModel.Tab, DeskClockFragment> mFragmentCache;

    /** The active fragment transaction if one exists. */
    private FragmentTransaction mCurrentTransaction;

    /** The current fragment displayed to the user. */
    private Fragment mCurrentPrimaryItem;

    FragmentTabPagerAdapter(DeskClock deskClock) {
        mDeskClock = deskClock;
        mFragmentCache = new ArrayMap<>(getCount());
        mFragmentManager = deskClock.getFragmentManager();
    }

    @Override
    public int getCount() {
        return UiDataModel.getUiDataModel().getTabCount();
    }

    /**
     * @param position the left-to-right index of the fragment to be returned
     * @return the fragment displayed at the given {@code position}
     */
    DeskClockFragment getDeskClockFragment(int position) {
        // Fetch the tab the UiDataModel reports for the position.
        final UiDataModel.Tab tab = UiDataModel.getUiDataModel().getTabAt(position);

        // First check the local cache for the fragment.
        DeskClockFragment fragment = mFragmentCache.get(tab);
        if (fragment != null) {
            return fragment;
        }

        // Next check the fragment manager; relevant when app is rebuilt after locale changes
        // because this adapter will be new and mFragmentCache will be empty, but the fragment
        // manager will retain the Fragments built on original application launch.
        fragment = (DeskClockFragment) mFragmentManager.findFragmentByTag(tab.name());
        if (fragment != null) {
            fragment.setFabContainer(mDeskClock);
            mFragmentCache.put(tab, fragment);
            return fragment;
        }

        // Otherwise, build the fragment from scratch.
        final String fragmentClassName = tab.getFragmentClassName();
        fragment = (DeskClockFragment) Fragment.instantiate(mDeskClock, fragmentClassName);
        fragment.setFabContainer(mDeskClock);
        mFragmentCache.put(tab, fragment);
        return fragment;
    }

    @Override
    public void startUpdate(ViewGroup container) {
        if (container.getId() == View.NO_ID) {
            throw new IllegalStateException("ViewPager with adapter " + this + " has no id");
        }
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        if (mCurrentTransaction == null) {
            mCurrentTransaction = mFragmentManager.beginTransaction();
        }

        // Use the fragment located in the fragment manager if one exists.
        final UiDataModel.Tab tab = UiDataModel.getUiDataModel().getTabAt(position);
        Fragment fragment = mFragmentManager.findFragmentByTag(tab.name());
        if (fragment != null) {
            mCurrentTransaction.attach(fragment);
        } else {
            fragment = getDeskClockFragment(position);
            mCurrentTransaction.add(container.getId(), fragment, tab.name());
        }

        if (fragment != mCurrentPrimaryItem) {
            FragmentCompat.setMenuVisibility(fragment, false);
            FragmentCompat.setUserVisibleHint(fragment, false);
        }

        return fragment;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        if (mCurrentTransaction == null) {
            mCurrentTransaction = mFragmentManager.beginTransaction();
        }
        final DeskClockFragment fragment = (DeskClockFragment) object;
        fragment.setFabContainer(null);
        mCurrentTransaction.detach(fragment);
    }

    @Override
    public void setPrimaryItem(ViewGroup container, int position, Object object) {
        final Fragment fragment = (Fragment) object;
        if (fragment != mCurrentPrimaryItem) {
            if (mCurrentPrimaryItem != null) {
                FragmentCompat.setMenuVisibility(mCurrentPrimaryItem, false);
                FragmentCompat.setUserVisibleHint(mCurrentPrimaryItem, false);
            }
            if (fragment != null) {
                FragmentCompat.setMenuVisibility(fragment, true);
                FragmentCompat.setUserVisibleHint(fragment, true);
            }
            mCurrentPrimaryItem = fragment;
        }
    }

    @Override
    public void finishUpdate(ViewGroup container) {
        if (mCurrentTransaction != null) {
            mCurrentTransaction.commitAllowingStateLoss();
            mCurrentTransaction = null;
            mFragmentManager.executePendingTransactions();
        }
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return ((Fragment) object).getView() == view;
    }
}