JSONParser Class

Signature

public Void clearCurrentToken()

Return Value

Type: Void

Usage

After this method is called, a call to hasCurrentToken returns false and a call to getCurrentToken returns null. You can retrieve the cleared token by calling getLastClearedToken.

Signature

public Blob getBlobValue()

Return Value

Type: Blob

Usage

The current token must be of type JSONToken.VALUE_STRING and must be Base64-encoded.

Signature

public Boolean getBooleanValue()

Return Value

Type: Boolean

Usage

The current token must be of type JSONToken.VALUE_TRUE or JSONToken.VALUE_FALSE.

String JSONContent =
    '{"isActive":true}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the Boolean value.
Boolean isActive = parser.getBooleanValue();

Signature

public String getCurrentName()

Return Value

Type: String

Usage

If the current token is of type JSONToken.FIELD_NAME, this method returns the same value as getText. If the current token is a value, this method returns the field name that precedes this token. For other values such as array values or root-level values, this method returns null.

The following example parses a sample JSON string. It advances to the field value and retrieves its corresponding field name.

Example

String JSONContent = '{"firstName":"John"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the field name for the current value.
String fieldName = parser.getCurrentName();
// Get the textual representation 
// of the value.
String fieldValue = parser.getText();

Signature

public System.JSONToken getCurrentToken()

Return Value

Type: System.JSONToken

Usage

String JSONContent = '{"firstName":"John"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the next token.
while (parser.nextToken() != null) {
    System.debug('Current token: ' +
        parser.getCurrentToken());
}

Signature

public Datetime getDatetimeValue()

Return Value

Type: Datetime

Usage

The current token must be of type JSONToken.VALUE_STRING and must represent a Datetime value in the ISO-8601 format.

String JSONContent =
'{"transactionDate":"2011-03-22T13:01:23"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the transaction date.
Datetime transactionDate = 
   parser.getDatetimeValue();

Signature

public Date getDateValue()

Return Value

Type: Date

Usage

The current token must be of type JSONToken.VALUE_STRING and must represent a Date value in the ISO-8601 format.

String JSONContent =
   '{"dateOfBirth":"2011-03-22"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the date of birth.
Date dob = parser.getDateValue();

Signature

public Decimal getDecimalValue()

Return Value

Type: Decimal

Usage

The current token must be of type JSONToken.VALUE_NUMBER_FLOAT or JSONToken.VALUE_NUMBER_INT and is a numerical value that can be converted to a value of type Decimal.

String JSONContent =
   '{"GPA":3.8}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the GPA score.
Decimal gpa = parser.getDecimalValue();

Signature

public Double getDoubleValue()

Return Value

Type: Double

Usage

The current token must be of type JSONToken.VALUE_NUMBER_FLOAT and is a numerical value that can be converted to a value of type Double.

String JSONContent =
   '{"GPA":3.8}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the GPA score.
Double gpa = parser.getDoubleValue();

Signature

public ID getIdValue()

Return Value

Type: ID

Usage

The current token must be of type JSONToken.VALUE_STRING and must be a valid ID.

String JSONContent =
   '{"recordId":"001R0000002nO6H"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the record ID.
ID recordID = parser.getIdValue();

Signature

public Integer getIntegerValue()

Return Value

Type: Integer

Usage

The current token must be of type JSONToken.VALUE_NUMBER_INT and must represent an Integer.

String JSONContent =
   '{"recordCount":10}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the record count.
Integer count = parser.getIntegerValue();

Signature

public System.JSONToken getLastClearedToken()

Return Value

Type: System.JSONToken

Signature

public Long getLongValue()

Return Value

Type: Long

Usage

The current token must be of type JSONToken.VALUE_NUMBER_INT and is a numerical value that can be converted to a value of type Long .

String JSONContent =
   '{"recordCount":2097531021}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the record count.
Long count = parser.getLongValue();

Signature

public String getText()

Return Value

Type: String

Usage

No current token exists, and therefore this method returns null, if nextToken has not been called yet for the first time or if the parser has reached the end of the input stream.

Signature

public Time getTimeValue()

Return Value

Type: Time

Usage

The current token must be of type JSONToken.VALUE_STRING and must represent a Time value in the ISO-8601 format.

String JSONContent =
   '{"arrivalTime":"18:05"}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Advance to the start object marker.
parser.nextToken();
// Advance to the next value.
parser.nextValue();
// Get the arrival time.
Time arrivalTime = parser.getTimeValue();

Signature

public Boolean hasCurrentToken()

Return Value

Type: Boolean

Signature

public System.JSONToken nextToken()

Return Value

Type: System.JSONToken

Usage

Advances the stream enough to determine the type of the next token, if any.

Signature

public System.JSONToken nextValue()

Return Value

Type: System.JSONToken

Usage

Advances the stream enough to determine the type of the next token that is of a value type, if any, including a JSON array and object start and end markers.

Signature

public Object readValueAs(System.Type apexType)

Parameters

apexType

Type: System.Type

The apexType argument specifies the type of the object that this method returns after deserializing the current value.

Return Value

Type: Object

Usage

If the JSON content contains attributes not present in the System.Type argument, such as a missing field or object, deserialization fails in some circumstances. When deserializing JSON content into a custom object or an sObject using Salesforce API version 34.0 or earlier, this method throws a runtime exception when passed extraneous attributes. When deserializing JSON content into an Apex class in any API version, or into an object in API version 35.0 or later, no exception is thrown. When no exception is thrown, this method ignores extraneous attributes and parses the rest of the JSON content.

Example

public class Person {
    public String name;
    public String phone;
}

// JSON string that contains a Person object.
String JSONContent =
    '{"person":{' + 
        '"name":"John Smith",' +
        '"phone":"555-1212"}}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Make calls to nextToken() 
// to point to the second
// start object marker.
parser.nextToken();
parser.nextToken();
parser.nextToken();
// Retrieve the Person object
// from the JSON string.
Person obj = 
   (Person)parser.readValueAs(
      Person.class);
System.assertEquals(
   obj.name, 'John Smith');
System.assertEquals(
   obj.phone, '555-1212');

Signature

public Object readValueAsStrict(System.Type apexType)

Parameters

apexType

Type: System.Type

The apexType argument specifies the type of the object that this method returns after deserializing the current value.

Return Value

Type: Object

Usage

If the JSON content contains attributes not present in the System.Type argument, such as a missing field or object, deserialization fails in some circumstances. When deserializing JSON content with extraneous attributes into an Apex class, this method throws an exception in all API versions. However, no exception is thrown when you use this method to deserialize JSON content into a custom object or an sObject.

public class Person {
    public String name;
    public String phone;
}

// JSON string that contains a Person object.
String JSONContent =
    '{"person":{' + 
        '"name":"John Smith",' +
        '"phone":"555-1212"}}';
JSONParser parser = 
   JSON.createParser(JSONContent);
// Make calls to nextToken() 
// to point to the second
// start object marker.
parser.nextToken();
parser.nextToken();
parser.nextToken();
// Retrieve the Person object
// from the JSON string.
Person obj = 
   (Person)parser.readValueAsStrict(
      Person.class);
System.assertEquals(
   obj.name, 'John Smith');
System.assertEquals(
   obj.phone, '555-1212');

Signature

public Void skipChildren()

Return Value

Type: Void