javax.json

Class JsonReader

java.lang.Object

javax.json.JsonReader

All Implemented Interfaces:

Closeable, AutoCloseable

public class JsonReader
extends Object
implements Closeable

A JSON reader that reads a JSON object or array from an input source.

For example, an empty JSON array can be created as follows:

 
 JsonReader jsonReader = new JsonReader(new StringReader("[]"));
 JsonArray array = jsonReader.readArray();
 jsonReader.close();
 
 

It uses JsonParser internally for parsing. The parser is created using one of the Json's createParser methods.

Author:

Jitendra Kotamraju

Constructor Summary

Constructors

Constructor and Description
JsonReader(InputStream in) Creates a JSON reader from a byte stream.
JsonReader(InputStream in, Charset charset) Creates a JSON reader from a byte stream.
JsonReader(InputStream in, Charset charset, JsonConfiguration config) Creates a JSON reader from a byte stream.
JsonReader(Reader reader) Creates a JSON reader from a character stream
JsonReader(Reader reader, JsonConfiguration config) Creates a JSON reader from a character stream

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes this reader and frees any resources associated with the reader.
JsonStructure	read() Returns a JSON array or object that is represented in the input source.
JsonArray	readArray() Returns a JSON array that is represented in the input source.
JsonObject	readObject() Returns a JSON object that is represented in the input source.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JsonReader

public JsonReader(Reader reader)

Creates a JSON reader from a character stream

Parameters:

reader - a reader from which JSON is to be read

JsonReader

public JsonReader(Reader reader,
          JsonConfiguration config)

Creates a JSON reader from a character stream

Parameters:

reader - a character stream from which JSON is to be read

config - configuration of the reader

Throws:

IllegalArgumentException - if a feature in the configuration is not known

JsonReader

public JsonReader(InputStream in)

Creates a JSON reader from a byte stream. The character encoding of the stream is determined as per the RFC.

Parameters:

in - a byte stream from which JSON is to be read

JsonReader

public JsonReader(InputStream in,
          Charset charset)

Creates a JSON reader from a byte stream. The bytes of the stream are decoded to characters using the specified charset.

Parameters:

in - a byte stream from which JSON is to be read

charset - a charset

JsonReader

public JsonReader(InputStream in,
          Charset charset,
          JsonConfiguration config)

Creates a JSON reader from a byte stream. The bytes of the stream are decoded to characters using the specified charset. The created reader is configured with the specified configuration.

Parameters:

in - a byte stream from which JSON is to be read

charset - a charset

config - configuration of the reader

Throws:

IllegalArgumentException - if a feature in the configuration is not known

Method Detail

read

public JsonStructure read()

Returns a JSON array or object that is represented in the input source. This method needs to be called only once for a reader instance.

Returns:

a Json object or array

Throws:

JsonException - if a JSON object or array cannot be created due to i/o error (IOException would be cause of JsonException)

JsonParsingException - if a JSON object or array cannot be created due to incorrect representation

IllegalStateException - if this method, readObject, readArray or close method is already called

readObject

public JsonObject readObject()

Returns a JSON object that is represented in the input source. This method needs to be called only once for a reader instance.

Returns:

a Json object

Throws:

JsonException - if a JSON object cannot be created due to i/o error (IOException would be cause of JsonException)

JsonParsingException - if a JSON object cannot be created due to incorrect representation

IllegalStateException - if this method, readObject, readArray or close method is already called

readArray

public JsonArray readArray()

Returns a JSON array that is represented in the input source. This method needs to be called only once for a reader instance.

Returns:

a Json array

Throws:

JsonException - if a JSON array cannot be created due to i/o error (IOException would be cause of JsonException)

JsonParsingException - if a JSON array cannot be created due to incorrect representation

IllegalStateException - if this method, readObject, readArray or close method is already called

close

public void close()

Closes this reader and frees any resources associated with the reader. This closes the underlying input source.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

JsonException - if an i/o error occurs (IOException would be cause of JsonException)