java.lang.Object 到 arraylist

Question

有没有办法可以将这种 java.lang.object 解析/转换为 java.lang.Object 的数组或列表:

[
    {procedure_name_txt=nameText, procedure_name_ets_id=ID-1234, procedure_ets_desc=description_123}, 
    {procedure_name_txt=deafness, procedure_name_ets_id=ID-99022, procedure_ets_desc=description_31222}
]

已经尝试使用 Gson，但不幸的是对象格式不是 json 形式。

Answer 1

由于多种原因，您提供的文档不是有效的 JSON:

• 数组元素键不包含在引号 " 中。
• 数组元素键/值对不使用 : 分隔，而是使用 = 分隔。
• 字符串值不包含在引号 " 中。

我几乎可以肯定该文档实际上是一个集合/数组的打印精美的 toString 结果，其元素是映射或覆盖了 toString 的 POJO。此类输出决不意味着以编程方式进行解析。然而，Gson 可以解析“tostring”结果，因为它的简单性违反了 JSON 格式语法并且过于宽松。

private static final String LOOKS_LIKE_JSON = "[\n" +
        "    {procedure_name_txt=nameText, procedure_name_ets_id=ID-1234, procedure_ets_desc=description_123}, \n" +
        "    {procedure_name_txt=deafness, procedure_name_ets_id=ID-99022, procedure_ets_desc=description_31222}\n" +
        "]";

//  private static final Type procedureListType = TypeToken.getParameterized(List.class, Procedure.class).getType();
private static final Type procedureListType = new TypeToken<List<Procedure>>() {
}.getType();

//  private static final Type procedureArrayType = Procedure[].class;
private static final Type procedureArrayType = new TypeToken<Procedure[]>() {
}.getType();

private static final Type stringToStringMapListType = new TypeToken<List<Map<String, String>>>() {
}.getType();

private static final Type stringToStringMapArrayType = new TypeToken<Map<String, String>[]>() {
}.getType();

private static final Gson gson = new Gson();
private static final JsonParser jsonParser = new JsonParser();

public static void main(final String... args) {
    final List<Procedure> procedureList = gson.fromJson(LOOKS_LIKE_JSON, procedureListType);
    System.out.println(procedureList);
    final Procedure[] procedureArray = gson.fromJson(LOOKS_LIKE_JSON, procedureArrayType);
    System.out.println(Arrays.toString(procedureArray));
    final List<Map<String, String>> mapList = gson.fromJson(LOOKS_LIKE_JSON, stringToStringMapListType);
    System.out.println(mapList);
    final Map<String, String>[] mapArray = gson.fromJson(LOOKS_LIKE_JSON, stringToStringMapArrayType);
    System.out.println(Arrays.toString(mapArray));
    final JsonElement jsonElement = jsonParser.parse(LOOKS_LIKE_JSON);
    System.out.println(jsonElement);
}

其中Procedure类如下:

final class Procedure {

    @SerializedName("procedure_name_txt")
    final String name = null;

    @SerializedName("procedure_name_ets_id")
    final String id = null;

    @SerializedName("procedure_ets_desc")
    final String description = null;

    @Override
    public String toString() {
        return new StringBuilder("Procedure{")
                .append("name='").append(name).append('\'')
                .append(", id='").append(id).append('\'')
                .append(", description='").append(description).append('\'')
                .append('}')
                .toString();
    }

}

输出:

• IntelliJ IDEA 生成的 Procedure.toString:

[Procedure{name='nameText', id='ID-1234', description='description_123'}, Procedure{name='deafness', id='ID-99022', description='description_31222'}]

• 字符串到字符串条目的映射列表(实际上这反射(reflect)了给定的输入)，JDK toString():

[{procedure_name_txt=nameText, procedure_name_ets_id=ID-1234, procedure_ets_desc=description_123}, {procedure_name_txt=deafness, procedure_name_ets_id=ID-99022, procedure_ets_desc=description_31222}]

• Gson JSON 树模型toString():

[{"procedure_name_txt":"nameText","procedure_name_ets_id":"ID-1234","procedure_ets_desc":"description_123"},{"procedure_name_txt":"deafness","procedure_name_ets_id":"ID-99022","procedure_ets_desc":"description_31222"}]