Java tutorial
/******************************************************************************* * Copyright 2013 Open mHealth * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. ******************************************************************************/ package org.openmhealth.reference.domain; import java.io.ByteArrayInputStream; import java.io.IOException; import java.util.regex.Pattern; import name.jenkins.paul.john.concordia.Concordia; import name.jenkins.paul.john.concordia.exception.ConcordiaException; import name.jenkins.paul.john.concordia.validator.ValidationController; import org.openmhealth.reference.exception.OmhException; import com.fasterxml.jackson.annotation.JacksonInject; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.fasterxml.jackson.databind.JsonNode; /** * <p> * A schema as defined by the Open mHealth specification. * </p> * * <p> * This class is immutable. * </p> * * @author John Jenkins */ public class Schema implements OmhObject { /** * The version of this class for serialization purposes. */ private static final long serialVersionUID = 1L; /** * The pattern to use for validating schema IDs. */ private static final Pattern PATTERN_ID = Pattern.compile("omh(:[a-zA-Z0-9_]+)+"); /** * The JSON key for the ID of a schema. */ public static final String JSON_KEY_ID = "schema_id"; /** * The JSON key for the version of the schema. */ public static final String JSON_KEY_VERSION = "schema_version"; /** * The JSON key for the Concordia schema. */ public static final String JSON_KEY_SCHEMA = "schema"; /** * The JSON key for the {@link ValidationController} that will be used to * build the underlying {@link Concordia} object. If not set or not given, * the default one, {@link ValidationController#BASIC_CONTROLLER} will be * used. */ public static final String JSON_KEY_VALIDATION_CONTROLLER = "validation_controller"; /** * The schema's ID. */ @JsonProperty(JSON_KEY_ID) private final String id; /** * The schema's version. */ @JsonProperty(JSON_KEY_VERSION) private final long version; /** * The actual schema for this {@link Schema} object. */ @JsonProperty(JSON_KEY_SCHEMA) private final Concordia schema; /** * Creates a new schema (registry entry). * * @param id * The ID for this schema. * * @param version * The version of this schema. * * @param schema * The specific schema. * * @param controller * The controller used to validate this schema and to validate any * data when using the * {@link #validateData(String, MetaData, JsonNode)} method. * * @throws OmhException * A parameter was invalid. * * @see #validateData(String, MetaData, JsonNode) */ @JsonCreator public Schema(@JsonProperty(JSON_KEY_ID) final String id, @JsonProperty(JSON_KEY_VERSION) final long version, @JsonProperty(JSON_KEY_SCHEMA) final JsonNode schema, @JacksonInject(JSON_KEY_VALIDATION_CONTROLLER) final ValidationController controller) throws OmhException { // Validate the ID. if (id == null) { throw new OmhException("The ID is null."); } else if (id.trim().length() == 0) { throw new OmhException("The ID is empty."); } else { this.id = validateId(id); } // Validate the version. this.version = validateVersion(version); // Make sure the schema is not null. if (schema == null) { throw new OmhException("The schema is null."); } try { this.schema = new Concordia(new ByteArrayInputStream(schema.toString().getBytes()), controller); } catch (IllegalArgumentException e) { throw new OmhException("The schema is missing.", e); } catch (ConcordiaException e) { throw new OmhException("The schema is invalid.", e); } catch (IOException e) { throw new OmhException("The schema cannot be read.", e); } } /** * Returns the unique identifier for this schema. * * @return The unique identifier for this schema. */ public String getId() { return id; } /** * Returns the version of this schema. * * @return The version of this schema. */ public long getVersion() { return version; } /** * Returns the schema. * * @return The schema. */ public Concordia getSchema() { return schema; } /** * Validates some data. * * @param owner * The owner of the data that is being validated. This is needed to * build the {@link Data} object. * * @param metaData * The meta-data for the data that is being validated. This is * needed to build the {@link Data} object. * * @param data * The data to be validated. * * @return The validated data as a {@link Data} object. * * @throws OmhException * The data was null or invalid. */ public Data validateData(final String owner, final MetaData metaData, final JsonNode data) throws OmhException { // Ensure the data is not null. if (data == null) { throw new OmhException("The data field is null."); } // Validate the data. try { schema.validateData(data); } catch (ConcordiaException e) { throw new OmhException("The data is invalid.", e); } // Return the result. return new Data(owner, this, metaData, data); } /** * Validates that the ID follows our rules. * * @param id * The ID to be validated. * * @return The validated and, potentially, simplified schema, e.g. trimmed. * * @throws OmhException * The ID is invalid. */ public static String validateId(final String id) throws OmhException { // Validate that the ID is not null. if (id == null) { throw new OmhException("The ID is null."); } // Remove surrounding whitespace. String idTrimmed = id.trim(); // Validate that the ID is not empty or only whitespace. if (idTrimmed.length() == 0) { throw new OmhException("The ID is empty or only whitespace."); } // Validate that the trimmed ID matches the pattern. if (!PATTERN_ID.matcher(idTrimmed).matches()) { throw new OmhException( "The schema ID is invalid. It must be colon " + "deliminated, alphanumeric sections, with or " + "without underscores, where the first section is " + "\"omh\": " + idTrimmed); } // Return the trimmed ID. return idTrimmed; } /** * Validates that the version follows our rules. * * @param version * The version to be validated. * * @return The version as it was given. * * @throws OmhException * The version is invalid. */ public static long validateVersion(final long version) throws OmhException { // The version must be positive. if (version <= 0) { throw new OmhException("The version must be positive."); } return version; } /** * Validates that the chunk size follows our rules. * * @param chunkSize * The chunk size to validate. * * @return The chunk size as it was given. * * @throws OmhException * The chunk size is invalid. */ public static long validateChunkSize(final long chunkSize) throws OmhException { // The chunk size must be positive. if (chunkSize <= 0) { throw new OmhException("The chunk size must be positive."); } return chunkSize; } }