本文整理了Java中org.json.JSONObject类的一些代码示例，展示了JSONObject类的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。JSONObject类的具体详情如下：
包路径：org.json.JSONObject
类名称：JSONObject

JSONObject介绍

[英]A modifiable set of name/value mappings. Names are unique, non-null strings. Values may be any mix of JSONObject, JSONArray, Strings, Booleans, Integers, Longs, Doubles or #NULL. Values may not be null, Double#isNaN(), Double#isInfinite(), or of any type not listed here.

This class can coerce values to another type when requested.

When the requested type is a boolean, strings will be coerced using a case-insensitive comparison to "true" and "false".
When the requested type is a double, other Number types will be coerced using Number#doubleValue(). Strings that can be coerced using Double#valueOf(String) will be.
When the requested type is an int, other Number types will be coerced using Number#intValue(). Strings that can be coerced using Double#valueOf(String) will be, and then cast to int.
When the requested type is a long, other Number types will be coerced using Number#longValue(). Strings that can be coerced using Double#valueOf(String) will be, and then cast to long. This two-step conversion is lossy for very large values. For example, the string "9223372036854775806" yields the long 9223372036854775807.
When the requested type is a String, other non-null values will be coerced using String#valueOf(Object). Although null cannot be coerced, the sentinel value JSONObject#NULL is coerced to the string "null".

This class can look up both mandatory and optional values:

Use getType() to retrieve a mandatory value. This fails with a JSONException if the requested name has no value or if the value cannot be coerced to the requested type.
Use optType() to retrieve an optional value. This returns a system- or user-supplied default if the requested name has no value or if the value cannot be coerced to the requested type.

Warning: this class represents null in two incompatible ways: the standard Java null reference, and the sentinel value JSONObject#NULL. In particular, calling put(name, null) removes the named entry from the object but put(name, JSONObject.NULL) stores an entry whose value is JSONObject.NULL.

Instances of this class are not thread safe. Although this class is nonfinal, it was not designed for inheritance and should not be subclassed. In particular, self-use by overrideable methods is not specified. See Effective Java Item 17, "Design and Document or inheritance or else prohibit it" for further information.
[中]可修改的名称/值映射集。名称是唯一的非空字符串。值可以是JSONObject、JSONArray、字符串、布尔、整数、长、双精度或#NULL的任意组合。值不能为null、Double#isNaN（）、Double#isInfinite（）或此处未列出的任何类型。
此类可以在请求时将值强制为其他类型。
*当请求的类型是布尔类型时，将使用不区分大小写的比较“true”和“false”强制字符串。
*当请求的类型为double时，将使用Number#doubleValue（）强制其他数字类型。可以使用Double#valueOf（String）强制的字符串将被删除。
*当请求的类型为int时，将使用Number#intValue（）强制其他数字类型。可以使用Double#valueOf（String）强制的字符串将为，然后强制转换为int。

When the requested type is a long, other Number types will be coerced using Number#longValue(). Strings that can be coerced using Double#valueOf(String) will be, and then cast to long. This two-step conversion is lossy for very large values. For example, the string "9223372036854775806" yields the long 9223372036854775807.
*当请求的类型是字符串时，将使用字符串#valueOf（Object）强制其他非空值。尽管不能强制null，但哨兵值JSONObject#null被强制为字符串“null”。
此类可以查找强制值和可选值：
*使用getType()检索强制值。如果请求的名称没有值，或者无法将值强制为请求的类型，则JSONException将失败。
*使用optType()检索可选值。如果请求的名称没有值，或者无法将值强制为请求的类型，则返回系统或用户提供的默认值。
警告：此类以两种不兼容的方式表示null：标准Java null引用和sentinel值JSONObject#null。特别是，调用put（name，null）会从对象中删除命名条目，但put（name，JSONObject.null）会存储一个值为JSONObject的条目。无效的
此类的实例不是线程安全的。虽然这个类是非最终类，但它不是为继承而设计的，不应该被子类化。特别是，未指定可重写方法的自用。有关更多信息，请参见有效的Java项目17“设计和文档或继承或禁止”。

代码示例

canonical example by Tabnine

public String creatingJsonString() {
  JSONArray pets = new JSONArray();
  pets.put("cat");
  pets.put("dog");
  JSONObject person = new JSONObject();
  person.put("name", "John Brown");
  person.put("age", 35);
  person.put("pets", pets);
  return person.toString(2);
}

canonical example by Tabnine

public void accessingJson(JSONObject json) {
  Object invalid = json.get("invalid"); // throws JSONException - "invalid" entry doesn't exists
  String name = json.getString("name"); // name = "John Brown"
  int number = json.getInt("name"); // throws JSONException - "name" entry isn't int
  int age = json.optInt("age", 42); // using default value instead of throwing exception
  JSONArray pets = json.getJSONArray("pets");
  for (int i = 0; i < pets.length(); i++) {
    String pet = pets.getString(i);
  }
}

org.json.JSONObject类的使用及代码示例

JSONObject介绍

代码示例

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JSONObject类方法