Android Charset Create charsetForVendor(String charsetName, String vendor)

Description

Returns the vendor-specific character set corresponding to the given original character set name and vendor.

License

Apache License

Parameter

Parameter	Description
charsetName	the base character set name
vendor	the vendor to specialize for

Exception

Parameter	Description
UnsupportedCharsetException	thrown if the named characterset is not supported by the system
IllegalCharsetNameException	thrown if charsetNamehas invalid syntax

Return

the specialized character set, or the one corresponding directly to charsetName if there is no specialized variant

Declaration

public static Charset charsetForVendor(String charsetName, String vendor)
        throws UnsupportedCharsetException, IllegalCharsetNameException

Method Source Code

//package com.java2s;
/*/*  ww w .j a v a 2s. c  o m*/
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

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;

public class Main {
    /**
     * 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>();

    /**
     * Returns 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 character set corresponding to the original
     * name. The vendor name is matched case-insensitively. This
     * method merely calls {@code Charset.forName()} on a name
     * transformed by a call to {@link #nameForVendor(String,String)}.
     * 
     * @param charsetName the base character set name
     * @param vendor the vendor to specialize for
     * @return the specialized character set, or the one corresponding
     * directly to {@code charsetName} if there is no specialized
     * variant
     * @throws UnsupportedCharsetException thrown if the named character
     * set is not supported by the system
     * @throws IllegalCharsetNameException thrown if {@code charsetName}
     * has invalid syntax
     */
    public static Charset charsetForVendor(String charsetName, String vendor)
            throws UnsupportedCharsetException, IllegalCharsetNameException {
        charsetName = nameForVendor(charsetName, vendor);
        return Charset.forName(charsetName);
    }

    /**
     * Returns the vendor-specific character set corresponding to the
     * given original character set name and default vendor (that is,
     * the targeted vendor of the device this code is running on). 
     * This method merely calls through to {@link
     * #charsetForVendor(String,String)}, passing the default vendor
     * as the second argument.
     * 
     * @param charsetName the base character set name
     * @return the specialized character set, or the one corresponding
     * directly to {@code charsetName} if there is no specialized
     * variant
     * @throws UnsupportedCharsetException thrown if the named character
     * set is not supported by the system
     * @throws IllegalCharsetNameException thrown if {@code charsetName}
     * has invalid syntax
     */
    public static Charset charsetForVendor(String charsetName)
            throws UnsupportedCharsetException, IllegalCharsetNameException {
        return charsetForVendor(charsetName, getDefaultVendor());
    }

    /**
     * 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.
     *
     * @param charsetName the base character set name
     * @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) {
        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;
    }

    /**
     * Gets the default vendor for this build.
     * 
     * @return the default vendor name
     */
    private static String getDefaultVendor() {
        return Build.BRAND;
    }

    /**
     * Returns whether the given character set name indicates the Shift-JIS
     * encoding. Returns false if the name is null.
     * 
     * @param charsetName the character set name
     * @return {@code true} if the name corresponds to Shift-JIS or
     * {@code false} if not
     */
    private static boolean isShiftJis(String charsetName) {
        // Bail quickly if the length doesn't match.
        if (charsetName == null) {
            return false;
        }
        int length = charsetName.length();
        if (length != 4 && length != 9) {
            return false;
        }

        return charsetName.equalsIgnoreCase("shift_jis")
                || charsetName.equalsIgnoreCase("shift-jis")
                || charsetName.equalsIgnoreCase("sjis");
    }
}