Java 将字段解析为对象或数组时出错
我有下面的Json字符串,我假设它是反序列化的。问题是:由于这个字符串来自服务器,我无法更改它,我需要反序列化为POJO。您可以看到,Java 将字段解析为对象或数组时出错,java,arrays,json,gson,Java,Arrays,Json,Gson,我有下面的Json字符串,我假设它是反序列化的。问题是:由于这个字符串来自服务器,我无法更改它,我需要反序列化为POJO。您可以看到,Grafs键对于每个子区域具有不同的值。一个是对象,另一个是数组。我该怎么办 { "Status": "true", "Result: { "rows": { "row": { "status": true, "subareas": [ {
Grafs
键对于每个子区域具有不同的值。一个是对象,另一个是数组。我该怎么办
{
"Status": "true",
"Result: {
"rows": {
"row": {
"status": true,
"subareas": [
{
"nome": "Associacao Utente",
"id": 9,
"grafs": {
"rows": {
"id": 6,
"nome": "Associacao Utente",
"tipo": "PIE",
"serv": "MV_AS_UTENTE_POR_NEGOCIO",
"periodo": "ANO"
}
}
}, {
"nome": "Chaves",
"id": 60,
"grafs": {
"rows": [
{
"id": 35,
"nome": "Chaves Criados por ano",
"tipo": "LINHA",
"serv": "MV_ASSOC_TOTAL_CHAVES",
"periodo": "ANO"
}, {
"id": 592,
"nome": "Chaves Associado Ao User Portal",
"tipo": "BAR",
"serv": "MV_ASSOC_USER_CHAVES",
"periodo": "TODOS"
}, {
"id": 593,
"nome": "Chaves Associado Ao Negocios",
"tipo": "BAR",
"serv": "MV_ASSOC_CHAVES",
"periodo": "TODOS"
}
]
}
}
]
}
}
}
}
下面是我的课程
public class Example {
private String Status;
private Result Result;
public String getStatus() {
return Status;
}
public void setStatus(String status) {
Status = status;
}
public Result getResult() {
return Result;
}
public void setResult(Result result) {
Result = result;
}
@Override
public String toString() {
return "Example [Status=" + Status + ", Result=" + Result + "]";
}
}
public class Result {
private Rows rows;
public Rows getRows() {
return rows;
}
public void setRows(Rows rows) {
this.rows = rows;
}
@Override
public String toString() {
return "Result [rows=" + rows + "]";
}
}
public class Grafs {
private List<Rows_> rows = new ArrayList<>();
public List<Rows_> getRows() {
return rows;
}
public void setRows(List<Rows_> Rows) {
this.rows = Rows;
}
@Override
public String toString() {
return "Grafs [rows=" + rows + "]";
}
}
public class Row {
private Boolean status;
private List<Subarea> subareas = new ArrayList<>();
public Boolean getStatus() {
return status;
}
public void setStatus(Boolean status) {
this.status = status;
}
public List<Subarea> getSubareas() {
return subareas;
}
public void setSubareas(List<Subarea> subareas) {
this.subareas = subareas;
}
@Override
public String toString() {
return "Row [status=" + status + ", subareas=" + subareas + "]";
}
}
public class Row_ {
private Integer id;
private String nome;
private String serv;
private String periodo;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public String getServ() {
return serv;
}
public void setServ(String serv) {
this.serv = serv;
}
public String getPeriodo() {
return periodo;
}
public void setPeriodo(String periodo) {
this.periodo = periodo;
}
@Override
public String toString() {
return "Row_ [id=" + id + ", nome=" + nome + ", serv=" + serv
+ ", periodo=" + periodo + "]";
}
}
public class Rows {
private Row row;
public Row getRow() {
return row;
}
public void setRow(Row row) {
this.row = row;
}
@Override
public String toString() {
return "Rows [row=" + row + "]";
}
}
public class Rows_ {
private Row_ row;
public Row_ getRow() {
return row;
}
public void setRow(Row_ row) {
this.row = row;
}
}
public class Subarea {
private String nome;
private Integer id;
private Grafs grafs;
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Grafs getGrafs() {
return grafs;
}
public void setGrafs(Grafs grafs) {
this.grafs = grafs;
}
@Override
public String toString() {
return "Subarea [nome=" + nome + ", id=" + id + ", grafs=" + grafs
+ "]";
}
}
我将Rows_uu声明为arraylist,但它遇到了一个对象。但第二行实际上是一个数组。我如何解决这个问题
带有一个元素的数组仍应呈现为数组。这就是我使用数组的原因。但它给出了我描述的错误
谢谢你的帮助。非常感谢。您可以用它来进行转换。下面是一个工厂,它将把该功能添加到您的所有列表成员类型中--
当我运行:run:gson2时,它使用TypeAdapterFactory给出这个输出。Example@caf0ed当然,构建成功(总时间:0秒),但我要打印转换后的Json:Gson Gson=builder.registerTypeAdapterFactory(新的SingletonListTypeAdapterFactory()).create();Example=gson.fromJson(json,Example.class);System.out.println(示例);它应该打印转换后的Json,而不是Example@caf0ed,对吗?如果在android上,它应该在logcat中打印,或者在IntelliJ IDEA中的“运行”窗口中打印。您发出的消息在“消息”窗口中。在调用JSON
以确认收到输出之前,是否可以打印一条消息?我忘了提到这一点。处理和粘贴代码时,它在这些行中给出了错误Type=typeToken.getType();如果(typeToken.getRawType()!=List.class | |!(type instanceof ParameterizedType)){return null;}type elementType=((ParameterizedType)type)。getActualTypeArguments()[0];TypeAdapter-elementAdapter=gson.getAdapter(TypeToken.get(elementType));它说的是不兼容的类型,Required java.lang.ProcessBuilder.Redirect.Type和find java.lang.reflect.Type。我修复了导入,但仍然存在此错误。我需要做的是使用字符串方法(我猜)以编程方式修复json字符串以使其统一。有关于如何做的线索吗?下面给出的解决方案对你有用吗?我有一本书。
Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 13 column 18.
import com.google.gson.Gson;
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.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Collections;
import java.util.List;
public class SingletonListTypeAdapterFactory implements TypeAdapterFactory {
public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> typeToken) {
Type type = typeToken.getType();
if (typeToken.getRawType() != List.class
|| !(type instanceof ParameterizedType)) {
return null;
}
Type elementType = ((ParameterizedType) type).getActualTypeArguments()[0];
TypeAdapter<?> elementAdapter = gson.getAdapter(TypeToken.get(elementType));
TypeAdapter<T> arrayAdapter = gson.getDelegateAdapter(this, typeToken);
return (TypeAdapter<T>) newSingtonListAdapter((TypeAdapter<Object>) elementAdapter, (TypeAdapter<List<Object>>) arrayAdapter);
}
private <E> TypeAdapter<List<E>> newSingtonListAdapter(
final TypeAdapter<E> elementAdapter,
final TypeAdapter<List<E>> arrayAdapter) {
return new TypeAdapter<List<E>>() {
public void write(JsonWriter out, List<E> value) throws IOException {
if(value == null || value.isEmpty()) {
out.nullValue();
} else if(value.size() == 1) {
elementAdapter.write(out, value.get(0));
} else {
arrayAdapter.write(out, value);
}
}
public List<E> read(JsonReader in) throws IOException {
if (in.peek() != JsonToken.BEGIN_ARRAY) {
E obj = elementAdapter.read(in);
return Collections.singletonList(obj);
}
return arrayAdapter.read(in);
}
};
}
}
Gson gson = new GsonBuilder().registerTypeAdapterFactory(new SingletonListTypeAdapterFactory())
.create();