Merge "Add KDDI/Softbank to available Shift_Jis mapping."

package android.util;

import android.os.Build;

import android.text.TextUtils;

import java.nio.charset.Charset;

import java.nio.charset.IllegalCharsetNameException;

import java.nio.charset.UnsupportedCharsetException;

import java.util.HashMap;

import java.util.Map;

/**

 * <p>

 * A class containing utility methods related to character sets. This

 * class is primarily useful for code that wishes to be vendor-aware

 * in its interpretation of Japanese encoding names.

 * in its interpretation of Japanese charset names (used in DoCoMo,

 * KDDI, and SoftBank).

 * </p>

 *

 * <p>As of this writing, the only vendor that is recognized by this

 * class is Docomo (identified case-insensitively as {@code "docomo"}).</p>

 * 

 * <b>Note:</b> This class is hidden in Cupcake, with a plan to

 * un-hide in Donut. This was done because the first deployment to use

 * this code is based on Cupcake, but the API had to be introduced

 * after the public API freeze for that release. The upshot is that

 * only system applications can safely use this class until Donut is

 * available.

 * <p>

 * <b>Note:</b> Developers will need to add an appropriate mapping for

 * each vendor-specific charset. You may need to modify the C libraries

 * like icu4c in order to let Android support an additional charset.

 * </p>

 *

 * @hide

 */

public final class CharsetUtils {

    /**

     * name of the vendor "Docomo". <b>Note:</b> This isn't a public

     * name of the vendor "DoCoMo". <b>Note:</b> This isn't a public

     * constant, in order to keep this class from becoming a de facto

     * reference list of vendor names.

     */

    private static final String VENDOR_DOCOMO = "docomo";

    /**

     * Name of the vendor "KDDI".

     */

    private static final String VENDOR_KDDI = "kddi";

    /**

     * Name of the vendor "SoftBank".

     */

    private static final String VENDOR_SOFTBANK = "softbank";

    /**

     * Represents one-to-one mapping from a vendor name to a charset specific to the vendor.

     */

    private static final Map<String, String> sVendorShiftJisMap = new HashMap<String, String>();

    static {

        // These variants of Shift_JIS come from icu's mapping data (convrtrs.txt)

        sVendorShiftJisMap.put(VENDOR_DOCOMO, "docomo-shift_jis-2007");

        sVendorShiftJisMap.put(VENDOR_KDDI, "kddi-shift_jis-2007");

        sVendorShiftJisMap.put(VENDOR_SOFTBANK, "softbank-shift_jis-2007");

    }

    /**

     * This class is uninstantiable.

     * Returns the name of the vendor-specific character set

     * corresponding to the given original character set name and

     * vendor. If there is no vendor-specific character set for the

     * given name/vendor pair, this returns the original character set

     * name. The vendor name is matched case-insensitively.

     * given name/vendor pair, this returns the original character set name.

     *

     * @param charsetName the base character set name

     * @param vendor the vendor to specialize for

     * @param vendor the vendor to specialize for. All characters should be lower-cased.

     * @return the specialized character set name, or {@code charsetName} if

     * there is no specialized name

     */

    public static String nameForVendor(String charsetName, String vendor) {

        // TODO: Eventually, this may want to be table-driven.

        if (vendor.equalsIgnoreCase(VENDOR_DOCOMO)

                && isShiftJis(charsetName)) {

            return "docomo-shift_jis-2007";

        if (!TextUtils.isEmpty(charsetName) && !TextUtils.isEmpty(vendor)) {

            // You can add your own mapping here.

            if (isShiftJis(charsetName)) {

                final String vendorShiftJis = sVendorShiftJisMap.get(vendor);

                if (vendorShiftJis != null) {

                    return vendorShiftJis;

                }

            }

        }

        return charsetName;