如何使用gson反序列化json到目前为止

时间:2014-09-25 11:57:16

标签: java json date gson

这是我的json:

  {
    "date": "14",
    "day": "1",
    "hours": "16",
    "minutes": "16",
    "month": "6",
    "seconds": "30",
    "time": "1405325790674",
    "timeInMicros": "1405325790674917",
    "timezoneOffset": "-480",
    "year": "114"
  }

这是我的代码

 Gson gson = new GsonBuilder().create();
 gson.fromJson(json, Date.class);

错误是

    com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected a string but was BEGIN_OBJECT at line 1 column 2
    at com.google.gson.Gson.fromJson(Gson.java:815)
    at com.google.gson.Gson.fromJson(Gson.java:768)
    at com.google.gson.Gson.fromJson(Gson.java:717)
    at com.google.gson.Gson.fromJson(Gson.java:689)
    at com.baidu.code.commit.TestConvertJson.test(TestConvertJson.java:26)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
    Caused by: java.lang.IllegalStateException: Expected a string but was BEGIN_OBJECT at line 1 column 2
    at com.google.gson.stream.JsonReader.nextString(JsonReader.java:821)
    at com.google.gson.internal.bind.DateTypeAdapter.read(DateTypeAdapter.java:66)
    at com.google.gson.internal.bind.DateTypeAdapter.read(DateTypeAdapter.java:41)
    at com.google.gson.Gson.fromJson(Gson.java:803)
    ... 28 more

1 个答案:

答案 0 :(得分:0)

这不是java.util.Date。你应该有一个Date类这样的

public class Date {
 private String date;
 private String day;
 private String hours;
 private String minutes;
 private String month;
 private String seconds;
 private String time;
 private String timeInMicros;
 private String timezoneOffset;
 private String year;

 // getters and setters
 }

现在您可以从此json消息中获取Date对象。

 String json="{\n" +
           "\n" +
           "    \"date\":\"14\",\n" +
           "    \"day\":\"1\",\n" +
           "    \"hours\":\"16\",\n" +
           "    \"minutes\":\"16\",\n" +
           "    \"month\":\"6\",\n" +
           "    \"seconds\":\"30\",\n" +
           "    \"time\":\"1405325790674\",\n" +
           "    \"timeInMicros\":\"1405325790674917\",\n" +
           "    \"timezoneOffset\":\"-480\",\n" +
           "    \"year\":\"114\"\n" +
           "\n" +
           "}";

   Date date=new Gson().fromJson(json,Date.class);