com.google.gwt.chrome.storage.Storage.java Source code

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Here is the source code for com.google.gwt.chrome.storage.Storage.java

Source

package com.google.gwt.chrome.storage;

import com.google.gwt.core.client.GWT;

public class Storage {

    public interface StorageChangeHandler {
        /**
         * Fired when one or more items change.
         * @param data Object mapping each key that changed to its corresponding StorageChange for that item.
         * @param area Name The name of the storage area ("sync" or "local") the changes are for.
         */
        void onChange(StorageChangeObject data, String areaName);
    }

    /**
     * Local storage area
     */
    public static final String LOCAL = "local";
    /**
     * Sync storage area
     */
    public static final String SYNC = "sync";
    /**
     * Flag if chrome storage API is available. If not it must use different interface implementation.
     */
    private final boolean isAvailable;

    private Storage(boolean isAvailable) {
        this.isAvailable = isAvailable;
    }

    private static StorageImpl impl = GWT.create(StorageImpl.class);

    /**
     * If extension's storage object if unavailable (is dev mode) it use message passing to background page instead 
     * @return Storage object. 
     */
    public static Storage getStorage() {
        if (impl.isAvailable()) {
            return new Storage(true);
        }
        return new Storage(false);
    }

    /**
     * Details about the error which occurred.
     * @return
     */
    public String getLastError() {
        return impl.getLastError();
    }

    /**
     * 
     * @return Items under the "local" storage area are local to each machine.
     */
    public LocalStorageArea getLocal() {
        return new LocalStorageArea(isAvailable);
    }

    /**
     * 
     * @return Items under the "sync" storage area are synced using Chrome Sync.
     */
    public SyncStorageArea getSync() {
        return new SyncStorageArea(isAvailable);
    }

    public void addChangeHandler(StorageChangeHandler handler) {
        impl.addChangeHandler(handler);
    }
}