com.hpzc.common.json.MyDateTypeAdapter.java Source code

Introduction

Here is the source code for com.hpzc.common.json.MyDateTypeAdapter.java

Source

package com.hpzc.common.json;

/*
 * Copyright (C) 2011 Google Inc.
 *
 * 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 com.google.gson.Gson;
import com.google.gson.JsonSyntaxException;
import com.google.gson.TypeAdapter;
import com.google.gson.TypeAdapterFactory;
import com.google.gson.reflect.TypeToken;
import com.google.gson.stream.JsonReader;
import com.google.gson.stream.JsonToken;
import com.google.gson.stream.JsonWriter;
import java.io.IOException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;

/**
 * Adapter for Date. Although this class appears stateless, it is not.
 * DateFormat captures its time zone and locale when it is created, which gives
 * this class state. DateFormat isn't thread safe either, so this class has
 * to synchronize its read and write methods.
 */
public final class MyDateTypeAdapter extends TypeAdapter<Date> {
    public static final TypeAdapterFactory FACTORY = new TypeAdapterFactory() {
        @SuppressWarnings("unchecked") // we use a runtime check to make sure the 'T's equal
        public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
            return typeToken.getRawType() == Date.class ? (TypeAdapter<T>) new MyDateTypeAdapter() : null;
        }
    };

    private final DateFormat df1 = new SimpleDateFormat("yyyy-MM-dd");
    private final DateFormat df2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    private final DateFormat df3 = buildIso8601Format();

    private static DateFormat buildIso8601Format() {
        DateFormat iso8601Format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.US);
        iso8601Format.setTimeZone(TimeZone.getTimeZone("UTC"));
        return iso8601Format;
    }

    @Override
    public Date read(JsonReader in) throws IOException {
        if (in.peek() == JsonToken.NULL) {
            in.nextNull();
            return null;
        }
        return deserializeToDate(in.nextString());
    }

    //   private boolean isNumeric(String str){
    //      Pattern p = Pattern.compile("[0-9]*");
    //      return p.matcher(str).matches();
    //    
    //   }

    private synchronized Date deserializeToDate(String json) {
        try {

            //        if(isNumeric(json))
            //{
            //long time = Long.parseLong(json);
            //return new Date(time);
            //}
            if (json.indexOf("T") > 0) {
                return df3.parse(json);
            } else if (json.indexOf(":") > 0) {
                return df2.parse(json);
            } else {
                return df1.parse(json);
            }
        } catch (ParseException e) {
            throw new JsonSyntaxException(json, e);
        }

        //    try {
        //      return df1.parse(json);
        //    } catch (ParseException ignored) {
        //    }
        //    try {
        //      return df2.parse(json);
        //    } catch (ParseException ignored) {
        //    }
        //    try {
        //      return df3.parse(json);
        //    } catch (ParseException e) {
        //      throw new JsonSyntaxException(json, e);
        //    }
    }

    @Override
    public synchronized void write(JsonWriter out, Date value) throws IOException {
        if (value == null) {
            out.nullValue();
            return;
        }
        String dateFormatAsString = df2.format(value);
        out.value(dateFormatAsString);
    }
}