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True. The JSONArray class provides two overloaded versions of the method named toJSONString . One is an instance method and the other is a static method. On a side note, this is also true of the class named JSONObject .
False. The code in Listing 2 produces the screen output shown in Figure 4 . Unlike an object of the JSONObject class, an object of the JSONArray class is an ordered list. By this we meanthat the user has precise control over where in the list each element is inserted. The user can access elements by their integer index (position in the list) .
False. The code in Listing 1 produces the screen output with the errors shown in Figure 2 . The JSONArray class neither defines nor inherits a method named put .
False. The JSONArray class extends the ArrayList class, which implements the List interface. Therefore, an object of the JSONArray class is a list and is not an array. For example, the elements in a JSONArray object cannot be accessed using the square bracket ([]) notation commonly associated with Java arrays. Instead, the elements are accessed using the add and get methods declared in the List interface and inherited from the ArrayList class.
False. The JSONArray class extends the standard Java ArrayList class.
This section contains Figures that may be referred to by one or more questions or answers.
Figure 1
[{"Name":"Tom"},{"Age":21},{"Student":true}] Figure 2
Code01.java:22: error: cannot find symbol
array.put(jsonObj01);^
symbol: method put(JSONObject)location: variable array of type JSONArray
Code01.java:23: error: cannot find symbolarray.put(jsonObj02);
^symbol: method put(JSONObject)
location: variable array of type JSONArrayCode01.java:24: error: cannot find symbol
array.put(jsonObj03);^
symbol: method put(JSONObject)location: variable array of type JSONArray
Note: Code01.java uses unchecked or unsafe operations.Note: Recompile with -Xlint:unchecked for details.
3 errorsError: Could not find or load main class Code01
Press any key to continue . . . Figure 3
[{"Name":"Tom"},{"Age":21},{"Student":true}] Figure 4
[{"Name":"Tom"},{"Student":true},{"Age":21}] Figure 5
[{"Name":"Tom"},{"Age":21},{"Student":true}]
[{"Name":"Tom"},{"Age":21},{"Student":true}] Figure 6
{"person":[{"Student":true},{"Age":21},{"Name":"Tom"}]} Figure 7
[{"Student":true},{"Age":21},{"Name":"Tom"}] Figure 8
{"person":[{"Name":"Tom"},{"Age":21},{"Name":"Tom"}]} This section contains Listings that may be referred to by one or more questions or answers.
Listing 1
/************************************************
Copyright: R.G.Baldwin 2016Tested with Java 8, Windows 7, and
json-simple-1.1.1.************************************************/
import org.json.simple.JSONObject;import org.json.simple.JSONArray;
class Code01{public static void main(String[] args){JSONObject jsonObj01 = new JSONObject();
jsonObj01.put("Name","Tom");JSONObject jsonObj02 = new JSONObject();
jsonObj02.put("Age",21);JSONObject jsonObj03 = new JSONObject();
jsonObj03.put("Student",true);JSONArray array = new JSONArray();array.put(jsonObj01);
array.put(jsonObj02);array.put(jsonObj03);
System.out.println(array.toJSONString());}//end main}//end class Code01 
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