在Android 项目中,可以把预先 JSON 数据保存在 res/raw 的目录下, 然后再通过Resources.openRawResource 读取。
Resources 对象可以通过Context 对象去获取。
public class Resources {
public InputStream openRawResource(@RawRes int id) throws NotFoundException {
public abstract class Context {
public abstract Resources getResources();
1. 保存json数据 (res/raw/ 目录下)
例如把 contents.json 保存在 res/raw 目录下
其中contents.json 的内容:
{
"pageInfo": {
"pageName": "abc",
"pagePic": "http://example.com/content.jpg"
},
"posts": [
{
"post_id": "123456789012_123456789012",
"actor_id": "1234567890",
"picOfPersonWhoPosted": "http://example.com/photo.jpg",
"nameOfPersonWhoPosted": "Jane Doe",
"message": "Sounds cool. Can't wait to see it!",
"likesCount": "2",
"comments": [],
"timeOfPost": "1234567890"
}
]
}
2. 导入Gson 依赖
略
3. 读取json 文件,得到 JsonObject 对象
private JsonObject load(int id){
String json = "";
try {
InputStream inputStream = mContext.getResources().openRawResource(id);
Writer writer = new StringWriter();
char[] buffer = new char[inputStream.available()];
Reader reader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
int n;
while((n = reader.read(buffer)) != -1){
log.info("load n="+n);
writer.write(buffer, 0, n);
}
json = writer.toString();
} catch (Exception e){
log.error("load json error: "+e.getMessage());
}
return new Gson().fromJson(json, JsonObject.class);
}
}
主要是得到InputStream后,通过BufferReader 读取, 最后写入到StringWriter 对象中。
4. 调用
JsonObject jsonObject = load(R.raw.contents);
其中, JsonObject 是Gson 依赖库的类, 也有JsonArray 表示数组, 注意区分org.json 库中的JSONObject 和JSONArray 类