Java tutorial
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However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.json; import java.io.Closeable; /** * Reads a JSON {@link JsonObject object} or an {@link JsonArray array} * structure from an input source. * * <p>The class {@link javax.json.Json} contains methods to create readers from * input sources ({@link java.io.InputStream} and {@link java.io.Reader}). * * <p> * The following example demonstrates how to read an empty JSON array from * a string: * <pre> * <code> * JsonReader jsonReader = Json.createReader(new StringReader("[]")); * JsonArray array = jsonReader.readArray(); * jsonReader.close(); * </code> * </pre> * * <p> * The class {@link JsonReaderFactory} also contains methods to create * {@code JsonReader} instances. A factory instance can be used to create * multiple reader instances with the same configuration. This the preferred * way to create multiple instances. A sample usage is shown in the following * example: * <pre> * <code> * JsonReaderFactory factory = Json.createReaderFactory(config); * JsonReader reader1 = factory.createReader(...); * JsonReader reader2 = factory.createReader(...); * </code> * </pre> */ public interface JsonReader extends /*Auto*/Closeable { /** * 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. * * @return 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) * @throws javax.json.stream.JsonParsingException if a JSON object or array * cannot be created due to incorrect representation * @throws IllegalStateException if read, readObject, readArray, * readValue or close method is already called */ JsonStructure read(); /** * Returns a JSON object that is represented in * the input source. This method needs to be called * only once for a reader instance. * * @return a JSON object * @throws JsonException if a JSON object cannot * be created due to i/o error (IOException would be * cause of JsonException) * @throws javax.json.stream.JsonParsingException if a JSON object cannot * be created due to incorrect representation * @throws IllegalStateException if read, readObject, readArray, * readValue or close method is already called */ JsonObject readObject(); /** * Returns a JSON array that is represented in * the input source. This method needs to be called * only once for a reader instance. * * @return a JSON array * @throws JsonException if a JSON array cannot * be created due to i/o error (IOException would be * cause of JsonException) * @throws javax.json.stream.JsonParsingException if a JSON array cannot * be created due to incorrect representation * @throws IllegalStateException if read, readObject, readArray, * readValue or close method is already called */ JsonArray readArray(); /** * Returns a JSON value that is represented in * the input source. This method needs to be called * only once for a reader instance. * * @return a JSON value * @throws JsonException if a JSON value * be created due to i/o error (IOException would be * cause of JsonException) * @throws javax.json.stream.JsonParsingException if a JSON value * cannot be created due to incorrect representation * @throws IllegalStateException if read, readObject, readArray, * readValue or close method is already called * * @since 1.1 */ default JsonValue readValue() { throw new UnsupportedOperationException(); } /** * Closes this reader and frees any resources associated with the * reader. This method closes the underlying input source. * * @throws JsonException if an i/o error occurs (IOException would be * cause of JsonException) */ @Override void close(); }