Java tutorial
/** * Global Sensor Networks (GSN) Source Code * Copyright (c) 2006-2014, Ecole Polytechnique Federale de Lausanne (EPFL) * * This file is part of GSN. * * GSN is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * GSN is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GSN. If not, see <http://www.gnu.org/licenses/>. * * File: src/gsn/beans/StreamElement.java * * @author rhietala * @author Timotee Maret * @author Sofiane Sarni * @author Ali Salehi * @author Mehdi Riahi * @author Julien Eberle * */ package gsn.beans; import gsn.http.rest.StreamElement4Rest; import gsn.utils.CaseInsensitiveComparator; import java.io.Serializable; import java.util.ArrayList; import java.util.TreeMap; import org.apache.commons.codec.binary.Base64; import org.slf4j.LoggerFactory; import org.slf4j.Logger; public final class StreamElement implements Serializable { private static final long serialVersionUID = 2000261462783698617L; private static final transient Logger logger = LoggerFactory.getLogger(StreamElement.class); private transient TreeMap<String, Integer> indexedFieldNames = null; private long timeStamp = -1; private String[] fieldNames; private Serializable[] fieldValues; private transient Byte[] fieldTypes; private transient long internalPrimayKey = -1; private static final String NULL_ENCODING = "NULL"; // null encoding for transmission over xml-rpc private boolean timestampProvided = false; public StreamElement(StreamElement other) { this.fieldNames = new String[other.fieldNames.length]; this.fieldValues = new Serializable[other.fieldValues.length]; this.fieldTypes = new Byte[other.fieldTypes.length]; for (int i = 0; i < other.fieldNames.length; i++) { fieldNames[i] = other.fieldNames[i]; fieldValues[i] = other.fieldValues[i]; fieldTypes[i] = other.fieldTypes[i]; } this.timeStamp = other.timeStamp; this.internalPrimayKey = other.internalPrimayKey; } public StreamElement() { //constructor for serialization } public StreamElement(DataField[] outputStructure, final Serializable[] data) { this(outputStructure, data, System.currentTimeMillis()); } public StreamElement(DataField[] outputStructure, final Serializable[] data, final long timeStamp) { this.fieldNames = new String[outputStructure.length]; this.fieldTypes = new Byte[outputStructure.length]; this.timeStamp = timeStamp; for (int i = 0; i < this.fieldNames.length; i++) { this.fieldNames[i] = outputStructure[i].getName().toLowerCase(); this.fieldTypes[i] = outputStructure[i].getDataTypeID(); } if (this.fieldNames.length != data.length) throw new IllegalArgumentException( "The length of dataFileNames and the actual data provided in the constructor of StreamElement doesn't match."); this.verifyTypesCompatibility(this.fieldTypes, data); this.fieldValues = data; } public StreamElement(final String[] dataFieldNames, final Byte[] dataFieldTypes, final Serializable[] data) { this(dataFieldNames, dataFieldTypes, data, System.currentTimeMillis()); } public StreamElement(final String[] dataFieldNames, final Byte[] dataFieldTypes, final Serializable[] data, final long timeStamp) { if (dataFieldNames.length != dataFieldTypes.length) throw new IllegalArgumentException( "The length of dataFileNames and dataFileTypes provided in the constructor of StreamElement doesn't match."); if (dataFieldNames.length != data.length) throw new IllegalArgumentException( "The length of dataFileNames and the actual data provided in the constructor of StreamElement doesn't match."); this.timeStamp = timeStamp; this.timestampProvided = true; this.fieldTypes = dataFieldTypes; this.fieldNames = dataFieldNames; this.fieldValues = data; this.verifyTypesCompatibility(dataFieldTypes, data); } public StreamElement(TreeMap<String, Serializable> output, DataField[] fields) { int nbFields = output.keySet().size(); if (output.containsKey("timed")) nbFields--; String fieldNames[] = new String[nbFields]; Byte fieldTypes[] = new Byte[nbFields]; Serializable fieldValues[] = new Serializable[nbFields]; TreeMap<String, Integer> indexedFieldNames = new TreeMap<String, Integer>(new CaseInsensitiveComparator()); int idx = 0; long timestamp = System.currentTimeMillis(); for (String key : output.keySet()) { Serializable value = output.get(key); if (key.equalsIgnoreCase("timed")) { timestamp = (Long) value; timestampProvided = true; } else { fieldNames[idx] = key; fieldValues[idx] = value; for (int i = 0; i < fields.length; i++) { if (fields[i].getName().equalsIgnoreCase(key)) fieldTypes[idx] = fields[i].getDataTypeID(); } indexedFieldNames.put(key, idx); idx++; } } this.fieldNames = fieldNames; this.fieldTypes = fieldTypes; this.fieldValues = fieldValues; this.indexedFieldNames = indexedFieldNames; this.timeStamp = timestamp; } /** * Verify if the data corresponds to the fieldType * @param fieldType * @param data * @throws IllegalArgumentException */ private void verifyTypeCompatibility(Byte fieldType, Serializable data) throws IllegalArgumentException { if (data == null) return; switch (fieldType) { case DataTypes.TINYINT: if (!(data instanceof Byte)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.SMALLINT: if (!(data instanceof Short)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.BIGINT: if (!(data instanceof Long)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.CHAR: case DataTypes.VARCHAR: if (!(data instanceof String)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.INTEGER: if (!(data instanceof Integer)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.DOUBLE: if (!(data instanceof Double || data instanceof Float)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.FLOAT: if (!(data instanceof Float)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; case DataTypes.BINARY: // if ( data[ i ] instanceof String ) data[ i ] = ( ( String ) // data[ i ] ).getBytes( ); if (!(data instanceof byte[] || data instanceof String)) throw new IllegalArgumentException("The field is defined as " + DataTypes.TYPE_NAMES[fieldType] + " while the actual data in the field is of type : *" + data.getClass().getCanonicalName() + "*"); break; } } /** * Checks the type compatibility of all fields of the StreamElement * @param fieldTypes the array of all fields' type * @param data the array of data to check * @throws IllegalArgumentException if a data field doesn't match the given type */ private void verifyTypesCompatibility(final Byte[] fieldTypes, final Serializable[] data) throws IllegalArgumentException { for (int i = 0; i < data.length; i++) { try { verifyTypeCompatibility(fieldTypes[i], data[i]); } catch (IllegalArgumentException e) { throw new IllegalArgumentException( "The newly constructed Stream Element is not consistent for the " + (i + 1) + "th field.", e); } } } public String toString() { final StringBuffer output = new StringBuffer("timed = "); output.append(this.getTimeStamp()).append("\t"); for (int i = 0; i < this.fieldNames.length; i++) output.append(",").append(this.fieldNames[i]).append("/").append(this.fieldTypes[i]).append(" = ") .append(this.fieldValues[i]); return output.toString(); } public final String[] getFieldNames() { return this.fieldNames; } /* * Returns the field types in GSN format. Checkout gsn.beans.DataTypes */ public final Byte[] getFieldTypes() { return this.fieldTypes; } public final Serializable[] getData() { return this.fieldValues; } public void setData(int index, Serializable data) { this.fieldValues[index] = data; } public long getTimeStamp() { return this.timeStamp; } public StringBuilder getFieldTypesInString() { final StringBuilder stringBuilder = new StringBuilder(); for (final byte i : this.getFieldTypes()) stringBuilder.append(DataTypes.TYPE_NAMES[i]).append(" , "); return stringBuilder; } /** * Returns true if the timestamp is set. A timestamp is valid if it is * set. * * @return Whether the timestamp is set or not. If it is >0 it is assumed to be set */ public boolean isTimestampSet() { return this.timeStamp > 0 || timestampProvided; } /** * Sets the time stamp of this stream element. * * @param timeStamp The time stamp value. If the timestamp is zero or * negative, it is considered non valid and zero will be placed. */ public void setTimeStamp(long timeStamp) { if (timeStamp <= 0) timeStamp = 0; else this.timeStamp = timeStamp; } /** * This method gets the attribute name as the input and returns the value * corresponding to that tuple. * * @param fieldName The name of the tuple. * @return The value corresponding to the named tuple. */ public final Serializable getData(final String fieldName) { generateIndex(); Integer index = indexedFieldNames.get(fieldName); if (index == null) { logger.warn("There is a request for field " + fieldName + " for StreamElement: " + this.toString() + ". As the requested field doesn't exist, GSN returns Null to the callee."); return null; } return this.fieldValues[index]; } /** * This method gets the attribute name as the input and returns the type of the value * corresponding to that tuple. * * @param fieldName The name of the tuple. * @return The type of the value corresponding to the named tuple. */ public final Byte getType(final String fieldName) { generateIndex(); Integer index = indexedFieldNames.get(fieldName); if (index == null) { logger.warn("There is a request for type of field " + fieldName + " for StreamElement: " + this.toString() + ". As the requested field doesn't exist, GSN returns Null to the callee."); return null; } return this.fieldTypes[index]; } public long getInternalPrimayKey() { return internalPrimayKey; } public void setInternalPrimayKey(long internalPrimayKey) { this.internalPrimayKey = internalPrimayKey; } /** * @return */ public Object[] getDataInRPCFriendly() { Object[] toReturn = new Object[fieldValues.length]; for (int i = 0; i < toReturn.length; i++) { //process null values if (fieldValues[i] == null) { toReturn[i] = NULL_ENCODING; continue; } switch (fieldTypes[i]) { case DataTypes.DOUBLE: case DataTypes.FLOAT: toReturn[i] = fieldValues[i]; break; case DataTypes.BIGINT: toReturn[i] = Long.toString((Long) fieldValues[i]); break; // case DataTypes.TIME : // toReturn[ i ] = Long.toString( ( Long ) fieldValues[ i ] ); // break; case DataTypes.TINYINT: case DataTypes.SMALLINT: case DataTypes.INTEGER: toReturn[i] = new Integer((Integer) fieldValues[i]); break; case DataTypes.CHAR: case DataTypes.VARCHAR: case DataTypes.BINARY: toReturn[i] = fieldValues[i]; break; default: logger.error("Type can't be converted : TypeID : " + fieldTypes[i]); } } return toReturn; } /** * Returns the type of the field in the output format or -1 if the field doesn't exit. * @param outputFormat * @param fieldName * @return */ private static byte findIndexInDataField(DataField[] outputFormat, String fieldName) { for (int i = 0; i < outputFormat.length; i++) if (outputFormat[i].getName().equalsIgnoreCase(fieldName)) return outputFormat[i].getDataTypeID(); return -1; } /*** * Used with the new JRuby/Mongrel/Rest interface */ public static StreamElement fromREST(DataField[] outputFormat, String[] fieldNames, String[] fieldValues, String timestamp) { Serializable[] values = new Serializable[outputFormat.length]; for (int i = 0; i < fieldNames.length; i++) { switch (findIndexInDataField(outputFormat, (String) fieldNames[i])) { case DataTypes.DOUBLE: values[i] = Double.parseDouble(fieldValues[i]); break; case DataTypes.FLOAT: values[i] = Float.parseFloat((String) fieldValues[i]); break; case DataTypes.BIGINT: // case DataTypes.TIME : values[i] = Long.parseLong((String) fieldValues[i]); break; case DataTypes.TINYINT: values[i] = Byte.parseByte((String) fieldValues[i]); break; case DataTypes.SMALLINT: case DataTypes.INTEGER: values[i] = Integer.parseInt(fieldValues[i]); break; case DataTypes.CHAR: case DataTypes.VARCHAR: values[i] = new String(Base64.decodeBase64(fieldValues[i].getBytes())); break; case DataTypes.BINARY: values[i] = (byte[]) Base64.decodeBase64(fieldValues[i].getBytes()); break; case -1: default: logger.error("The field name doesn't exit in the output structure : FieldName : " + (String) fieldNames[i]); } } return new StreamElement(outputFormat, values, Long.parseLong(timestamp)); } public static StreamElement createElementFromREST(DataField[] outputFormat, String[] fieldNames, Object[] fieldValues) { ArrayList<Serializable> values = new ArrayList<Serializable>(); // ArrayList<String> fields = new ArrayList<String>(); long timestamp = -1; for (int i = 0; i < fieldNames.length; i++) { if (fieldNames[i].equalsIgnoreCase("TIMED")) { timestamp = Long.parseLong((String) fieldValues[i]); continue; } boolean found = false; for (DataField f : outputFormat) { if (f.getName().equalsIgnoreCase(fieldNames[i])) { // fields.add(fieldNames[i]); found = true; break; } } if (found == false) continue; switch (findIndexInDataField(outputFormat, fieldNames[i])) { case DataTypes.DOUBLE: values.add(Double.parseDouble((String) fieldValues[i])); break; case DataTypes.FLOAT: values.add(Float.parseFloat((String) fieldValues[i])); break; case DataTypes.BIGINT: values.add(Long.parseLong((String) fieldValues[i])); break; case DataTypes.TINYINT: values.add(Byte.parseByte((String) fieldValues[i])); break; case DataTypes.SMALLINT: values.add(Short.parseShort((String) fieldValues[i])); break; case DataTypes.INTEGER: values.add(Integer.parseInt((String) fieldValues[i])); break; case DataTypes.CHAR: case DataTypes.VARCHAR: values.add(new String((byte[]) fieldValues[i])); break; case DataTypes.BINARY: try { // StreamElementTest.md5Digest(fieldValues[ i ]); } catch (Exception e) { logger.error(e.getMessage(), e); } values.add((byte[]) fieldValues[i]); break; case -1: default: logger.error("The field name doesn't exit in the output structure : FieldName : " + (String) fieldNames[i]); } } if (timestamp == -1) timestamp = System.currentTimeMillis(); return new StreamElement(outputFormat, values.toArray(new Serializable[] {}), timestamp); } public StreamElement4Rest toRest() { StreamElement4Rest toReturn = new StreamElement4Rest(this); return toReturn; } /** * Build the index for mapping field name to their positions in the array if it is not yet built * This assumes that StreamElements cannot change their structure */ private void generateIndex() { if (indexedFieldNames == null) { indexedFieldNames = new TreeMap<String, Integer>(new CaseInsensitiveComparator()); for (int i = 0; i < this.fieldNames.length; i++) this.indexedFieldNames.put(fieldNames[i], i); } } /** * set the data in the coresponding field, throws an exception if the data type doesn't match * @param fieldName * @param data * @throws IllegalArgumentException */ protected void setData(String fieldName, Serializable data) throws IllegalArgumentException { generateIndex(); Integer index = indexedFieldNames.get(fieldName); if (index == null) { logger.warn("There is a request for setting field " + fieldName + " for StreamElement: " + this.toString() + ". But the requested field doesn't exist."); } verifyTypeCompatibility(fieldTypes[index], data); setData(index, data); } }