fix sonarlint issues, add IDerivedWaveform interface

plugins/com.minres.scviewer.database.sqlite/src/com/minres/scviewer/database/sqlite/SQLiteDbLoader.java

@@ -13,7 +13,6 @@ package com.minres.scviewer.database.sqlite;
 import java.beans.IntrospectionException;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import java.sql.SQLException;
@@ -24,6 +23,7 @@ import java.util.List;
 import com.minres.scviewer.database.IWaveform;
 import com.minres.scviewer.database.IWaveformDb;
 import com.minres.scviewer.database.IWaveformDbLoader;
+import com.minres.scviewer.database.InputFormatException;
 import com.minres.scviewer.database.RelationType;
 import com.minres.scviewer.database.sqlite.db.IDatabase;
 import com.minres.scviewer.database.sqlite.db.SQLiteDatabase;
@@ -42,16 +42,13 @@ public class SQLiteDbLoader implements IWaveformDbLoader {
 	
 	private ScvSimProps scvSimProps;
 		
-	public SQLiteDbLoader() {
-	}
-
 	@Override
 	public Long getMaxTime() {
-		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<ScvTxEvent>(ScvTxEvent.class,
+		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<>(ScvTxEvent.class,
 				database, "time = (SELECT MAX(time) FROM ScvTxEvent)");
 		try {
 			List<ScvTxEvent> event = handler.selectObjects();
-			if(event.size()>0)
+			if(!event.isEmpty())
 				return event.get(0).getTime()*scvSimProps.getTime_resolution();
 		} catch (SecurityException | IllegalArgumentException | InstantiationException | IllegalAccessException
 				| InvocationTargetException | SQLException | IntrospectionException e) {
@@ -62,8 +59,8 @@ public class SQLiteDbLoader implements IWaveformDbLoader {
 
 	@Override
 	public Collection<IWaveform> getAllWaves() {
-		SQLiteDatabaseSelectHandler<ScvStream> handler = new SQLiteDatabaseSelectHandler<ScvStream>(ScvStream.class, database);
+		SQLiteDatabaseSelectHandler<ScvStream> handler = new SQLiteDatabaseSelectHandler<>(ScvStream.class, database);
-		List<IWaveform> streams=new ArrayList<IWaveform>();
+		List<IWaveform> streams=new ArrayList<>();
 		try {
 			for(ScvStream scvStream:handler.selectObjects()){
 				TxStream stream = new TxStream(database, db, scvStream);
@@ -72,7 +69,6 @@ public class SQLiteDbLoader implements IWaveformDbLoader {
 			}
 		} catch (SecurityException | IllegalArgumentException | InstantiationException | IllegalAccessException
 				| InvocationTargetException | SQLException | IntrospectionException e) {
-//			e.printStackTrace();
 		}
 		return streams;
 	}
@@ -80,25 +76,21 @@ public class SQLiteDbLoader implements IWaveformDbLoader {
 	private byte[] x = "SQLite format 3".getBytes();
 
 	@Override
-	public boolean load(IWaveformDb db, File file) throws Exception {
+	public boolean load(IWaveformDb db, File file) throws InputFormatException {
 		if(file.isDirectory() || !file.exists()) return false;
 		this.db=db;
-		try {
+		try(FileInputStream fis = new FileInputStream(file)) {
-			FileInputStream fis = new FileInputStream(file);
 			byte[] buffer = new byte[x.length];
 			int read = fis.read(buffer, 0, x.length);
-			fis.close();
 			if (read == x.length)
 				for (int i = 0; i < x.length; i++)
 					if (buffer[i] != x[i])	return false;
-		} catch(FileNotFoundException e) {
+		} catch(IOException e) {
-			return false;
-		} catch(IOException e) { //if an I/O error occurs
 			return false;
 		}
 		database=new SQLiteDatabase(file.getAbsolutePath());
 		database.setData("TIMERESOLUTION", 1L);
-		SQLiteDatabaseSelectHandler<ScvSimProps> handler = new SQLiteDatabaseSelectHandler<ScvSimProps>(ScvSimProps.class, database);
+		SQLiteDatabaseSelectHandler<ScvSimProps> handler = new SQLiteDatabaseSelectHandler<>(ScvSimProps.class, database);
 		try {
 			for(ScvSimProps simProps:handler.selectObjects()){
 				scvSimProps=simProps;

plugins/com.minres.scviewer.database.sqlite/src/com/minres/scviewer/database/sqlite/Tx.java

@@ -38,8 +38,10 @@ public class Tx implements ITx {
 	private TxGenerator trGenerator;
 	private ScvTx scvTx;
 	private List<ITxAttribute> attributes;
-	private Long begin, end;
+	private Long begin;
-	private List<ITxRelation> incoming, outgoing;
+	private Long end;
+	private List<ITxRelation> incoming;
+	private List<ITxRelation> outgoing;
 	
 	public Tx(IDatabase database, TxStream trStream, TxGenerator trGenerator, ScvTx scvTx) {
 		this.database=database;
@@ -71,7 +73,7 @@ public class Tx implements ITx {
 	@Override
 	public Long getBeginTime() {
 		if(begin==null){
-		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<ScvTxEvent>(ScvTxEvent.class,
+		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<>(ScvTxEvent.class,
 				database, "tx="+scvTx.getId()+" AND type="+ AssociationType.BEGIN.ordinal());
 		try {
 			for(ScvTxEvent scvEvent:handler.selectObjects()){
@@ -87,7 +89,7 @@ public class Tx implements ITx {
 	@Override
 	public Long getEndTime() {
 		if(end==null){
-		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<ScvTxEvent>(ScvTxEvent.class,
+		SQLiteDatabaseSelectHandler<ScvTxEvent> handler = new SQLiteDatabaseSelectHandler<>(ScvTxEvent.class,
 				database, "tx="+scvTx.getId()+" AND type="+ AssociationType.END.ordinal());
 		try {
 			for(ScvTxEvent scvEvent:handler.selectObjects()){
@@ -103,10 +105,10 @@ public class Tx implements ITx {
 	@Override
 	public List<ITxAttribute> getAttributes() {
 		if(attributes==null){
-			SQLiteDatabaseSelectHandler<ScvTxAttribute> handler = new SQLiteDatabaseSelectHandler<ScvTxAttribute>(
+			SQLiteDatabaseSelectHandler<ScvTxAttribute> handler = new SQLiteDatabaseSelectHandler<>(
 					ScvTxAttribute.class, database, "tx="+scvTx.getId());
 			try {
-				attributes = new ArrayList<ITxAttribute>();
+				attributes = new ArrayList<>();
 				for(ScvTxAttribute scvAttribute:handler.selectObjects()){
 					attributes.add(new TxAttribute(this, scvAttribute));
 					
@@ -121,10 +123,10 @@ public class Tx implements ITx {
 	@Override
 	public Collection<ITxRelation> getIncomingRelations() {
 		if(incoming==null){
-			SQLiteDatabaseSelectHandler<ScvTxRelation> handler = new SQLiteDatabaseSelectHandler<ScvTxRelation>(
+			SQLiteDatabaseSelectHandler<ScvTxRelation> handler = new SQLiteDatabaseSelectHandler<>(
 					ScvTxRelation.class, database, "sink="+scvTx.getId());
 			try {
-				incoming = new ArrayList<ITxRelation>();
+				incoming = new ArrayList<>();
 				for(ScvTxRelation scvRelation:handler.selectObjects()){
 					incoming.add(createRelation(scvRelation, false));
 				}
@@ -138,10 +140,10 @@ public class Tx implements ITx {
 	@Override
 	public Collection<ITxRelation> getOutgoingRelations() {
 		if(outgoing==null){
-			SQLiteDatabaseSelectHandler<ScvTxRelation> handler = new SQLiteDatabaseSelectHandler<ScvTxRelation>(
+			SQLiteDatabaseSelectHandler<ScvTxRelation> handler = new SQLiteDatabaseSelectHandler<>(
 					ScvTxRelation.class, database, "src="+scvTx.getId());
 			try {
-				outgoing = new ArrayList<ITxRelation>();
+				outgoing = new ArrayList<>();
 				for(ScvTxRelation scvRelation:handler.selectObjects()){
 					outgoing.add(createRelation(scvRelation, true));
 				}
@@ -154,7 +156,7 @@ public class Tx implements ITx {
 
 	private ITxRelation createRelation(ScvTxRelation rel, boolean outgoing) {
 		int otherId = outgoing?rel.getSink():rel.getSrc();
-		SQLiteDatabaseSelectHandler<ScvTx> handler = new SQLiteDatabaseSelectHandler<ScvTx>(ScvTx.class, database,
+		SQLiteDatabaseSelectHandler<ScvTx> handler = new SQLiteDatabaseSelectHandler<>(ScvTx.class, database,
 				"id="+otherId);
 		try {
 			List<ScvTx> res = handler.selectObjects();

plugins/com.minres.scviewer.database.sqlite/src/com/minres/scviewer/database/sqlite/TxGenerator.java

@@ -10,6 +10,7 @@
  *******************************************************************************/
 package com.minres.scviewer.database.sqlite;
 
+import java.util.ArrayList;
 import java.util.List;
 
 import com.minres.scviewer.database.IWaveform;
@@ -45,7 +46,7 @@ public class TxGenerator implements ITxGenerator {
 
 	@Override
 	public List<ITx> getTransactions() {
-		return null;
+		return new ArrayList<>();
 	}
 
 }

plugins/com.minres.scviewer.database.sqlite/src/com/minres/scviewer/database/sqlite/TxRelation.java

@@ -17,7 +17,8 @@ import com.minres.scviewer.database.tx.ITxRelation;
 public class TxRelation implements ITxRelation {
 
 	RelationType relationType;
-	Tx source, target;
+	Tx source;
+	Tx target;
 
 	public TxRelation(RelationType relationType, Tx source, Tx target) {
 		this.source = source;

plugins/com.minres.scviewer.database.sqlite/src/com/minres/scviewer/database/sqlite/TxStream.java

@@ -80,9 +80,9 @@ public class TxStream extends HierNode implements IWaveform {
 
 	public List<ITxGenerator> getGenerators() {
 		if(generators==null){
-			SQLiteDatabaseSelectHandler<ScvGenerator> handler = new SQLiteDatabaseSelectHandler<ScvGenerator>(
+			SQLiteDatabaseSelectHandler<ScvGenerator> handler = new SQLiteDatabaseSelectHandler<>(
 					ScvGenerator.class, database, "stream="+scvStream.getId());
-			generators=new TreeMap<Integer, TxGenerator>();
+			generators=new TreeMap<>();
 			try {
 				for(ScvGenerator scvGenerator:handler.selectObjects()){
 					generators.put(scvGenerator.getId(), new TxGenerator(this, scvGenerator));
@@ -92,22 +92,20 @@ public class TxStream extends HierNode implements IWaveform {
 				e.printStackTrace();
 			}
 		}
-		return new ArrayList<ITxGenerator>(generators.values());
+		return new ArrayList<>(generators.values());
 	}
 
 	@Override
 	public int getWidth() {
 		if(maxConcurrency==null){
-			java.sql.Connection connection=null;
-			java.sql.Statement statement=null;
-			java.sql.ResultSet resultSet=null;
-			try {
-				connection = database.createConnection();
-				statement = connection.createStatement();
 			StringBuilder sb = new StringBuilder();
 			sb.append("SELECT MAX(concurrencyLevel) as concurrencyLevel FROM ScvTx where stream=");
 			sb.append(scvStream.getId());
-				resultSet = statement.executeQuery(sb.toString());
+			try(
+					java.sql.Connection connection = database.createConnection();
+					java.sql.Statement statement = connection.createStatement();
+					java.sql.ResultSet resultSet = statement.executeQuery(sb.toString());
+					) {
 				while (resultSet.next()) {
 					if(maxConcurrency==null) maxConcurrency=0;
 					Object value = resultSet.getObject("concurrencyLevel");
@@ -116,12 +114,6 @@ public class TxStream extends HierNode implements IWaveform {
 				}
 			} catch (SQLException e) {
 				if(maxConcurrency==null) maxConcurrency=0;
-			} finally {
-				try{
-				if(resultSet!=null) resultSet.close();
-				if(statement!=null) statement.close();
-				if(connection!=null) connection.close();
-				} catch (SQLException e) {	}
 			}
 			maxConcurrency+=1;
 		}
@@ -131,7 +123,7 @@ public class TxStream extends HierNode implements IWaveform {
 	@Override
 	public  NavigableMap<Long, IEvent[]> getEvents(){
 		if(events==null){
-			events=new TreeMap<Long, IEvent[]>();
+			events=new TreeMap<>();
 			for(Entry<Integer, ITx> entry:getTransactions().entrySet()){
 				putEvent(new TxEvent(EventKind.BEGIN, entry.getValue()));
 				putEvent(new TxEvent(EventKind.END, entry.getValue()));
@@ -156,8 +148,8 @@ public class TxStream extends HierNode implements IWaveform {
 	protected Map<Integer, ITx> getTransactions() {
 		if(transactions==null){
 			if(generators==null) getGenerators();
-			transactions = new TreeMap<Integer, ITx>();
+			transactions = new TreeMap<>();
-			SQLiteDatabaseSelectHandler<ScvTx> handler = new SQLiteDatabaseSelectHandler<ScvTx>(ScvTx.class, database,
+			SQLiteDatabaseSelectHandler<ScvTx> handler = new SQLiteDatabaseSelectHandler<>(ScvTx.class, database,
 					"stream="+scvStream.getId());
 			try {
 				for(ScvTx scvTx:handler.selectObjects()){
@@ -187,7 +179,7 @@ public class TxStream extends HierNode implements IWaveform {
 	}
 
 	@Override
-	public Boolean equals(IWaveform other) {
+	public boolean isSame(IWaveform other) {
 		return(other instanceof TxStream && this.getId().equals(other.getId()));
 	}
 
@@ -195,7 +187,7 @@ public class TxStream extends HierNode implements IWaveform {
 	public IEvent[] getEventsBeforeTime(Long time) {
 		Entry<Long, IEvent[]> e = events.floorEntry(time);
 		if(e==null)
-    		return null;
+			return new IEvent[]{};
 		else
 			return  events.floorEntry(time).getValue();
 	}

plugins/com.minres.scviewer.database.text/src/com/minres/scviewer/database/text/TextDbLoader.groovy

@@ -25,6 +25,7 @@ import com.minres.scviewer.database.DataType
 import com.minres.scviewer.database.IWaveform
 import com.minres.scviewer.database.IWaveformDb
 import com.minres.scviewer.database.IWaveformDbLoader
+import com.minres.scviewer.database.InputFormatException
 import com.minres.scviewer.database.RelationType
 import com.minres.scviewer.database.tx.ITxGenerator
 
@@ -62,7 +63,7 @@ public class TextDbLoader implements IWaveformDbLoader{
 	static final byte[] x = "scv_tr_stream".bytes
 
 	@Override
-	boolean load(IWaveformDb db, File file) throws Exception {
+	boolean load(IWaveformDb db, File file) throws InputFormatException {
 		if(file.isDirectory() || !file.exists()) return false;
 		this.db=db
 		this.streams=[]

plugins/com.minres.scviewer.database.text/src/com/minres/scviewer/database/text/TxEvent.java

@@ -33,11 +33,6 @@ class TxEvent implements ITxEvent {
 		return new TxEvent(kind, transaction, time);
 	}
 
-//	@Override
-//	int compareTo(IWaveformEvent o) {
-//		time.compareTo(o.time)
-//	}
-
 	@Override
 	public
 	String toString() {

plugins/com.minres.scviewer.database.text/src/com/minres/scviewer/database/text/TxStream.groovy

@@ -114,7 +114,7 @@ class TxStream extends HierNode implements IWaveform {
 	}
 	
 	@Override
-	public Boolean equals(IWaveform other) {
+	public boolean isSame(IWaveform other) {
 		return(other instanceof TxStream && this.getId()==other.getId());
 	}
 

plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/WaveformView.java

@@ -1184,7 +1184,7 @@ public class WaveformView implements IWaveformView  {
 
 	public TrackEntry getEntryForStream(IWaveform source) {
 		for(TrackEntry trackEntry:streams)
-			if(trackEntry.waveform.equals(source)) return trackEntry;
+			if(trackEntry.waveform.isSame(source)) return trackEntry;
 		return null;
 	}
 

plugins/com.minres.scviewer.database.vcd/src/com/minres/scviewer/database/vcd/VCDDbLoader.java

@@ -14,11 +14,11 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.ArrayDeque;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.NavigableMap;
-import java.util.Stack;
 import java.util.TreeMap;
 import java.util.Vector;
 import java.util.zip.GZIPInputStream;
@@ -39,13 +39,13 @@ public class VCDDbLoader implements IWaveformDbLoader, IVCDDatabaseBuilder {
 
 
 	/** The Constant TIME_RES. */
-	private static final Long TIME_RES = 1000L; // ps;
+	private static final Long TIME_RES = 1000L; // ps
 
 	/** The db. */
 	private IWaveformDb db;
 
 	/** The module stack. */
-	private Stack<String> moduleStack;
+	private ArrayDeque<String> moduleStack;
 
 	/** The signals. */
 	private List<IWaveform> signals;
@@ -53,23 +53,14 @@ public class VCDDbLoader implements IWaveformDbLoader, IVCDDatabaseBuilder {
 	/** The max time. */
 	private long maxTime;
 
-	/**
-	 * Instantiates a new VCD db.
-	 */
-	public VCDDbLoader() {
-	}
-
 	private static boolean isGzipped(File f) {
-		InputStream is = null;
+		try (InputStream is = new FileInputStream(f)) {
-		try {
-			is = new FileInputStream(f);
 			byte [] signature = new byte[2];
 			int nread = is.read( signature ); //read the gzip signature
 			return nread == 2 && signature[ 0 ] == (byte) 0x1f && signature[ 1 ] == (byte) 0x8b;
-		} catch (IOException e) {
+		}
+		catch (IOException e) {
 			return false;
-		} finally {
-			try { is.close();} catch (IOException e) { }
 		}
 	}
 
@@ -79,21 +70,27 @@ public class VCDDbLoader implements IWaveformDbLoader, IVCDDatabaseBuilder {
 	 */
 	@SuppressWarnings("unchecked")
 	@Override
-	public boolean load(IWaveformDb db, File file) throws Exception {
+	public boolean load(IWaveformDb db, File file) throws InputFormatException {
 		if(file.isDirectory() || !file.exists()) return false;
 		this.db=db;
 		this.maxTime=0;
+		boolean res = false;
+		try {
 			String name = file.getCanonicalFile().getName();
 			if(!(name.endsWith(".vcd") ||
 					name.endsWith(".vcdz") ||
 					name.endsWith(".vcdgz")  ||
 					name.endsWith(".vcd.gz")) )
 				return false;
-		signals = new Vector<IWaveform>();
+			signals = new Vector<>();
-		moduleStack= new Stack<String>();
+			moduleStack= new ArrayDeque<>();
 			FileInputStream fis = new FileInputStream(file);
-		boolean res = new VCDFileParser(false).load(isGzipped(file)?new GZIPInputStream(fis):fis, this);
+			res = new VCDFileParser(false).load(isGzipped(file)?new GZIPInputStream(fis):fis, this);
 			moduleStack=null;
+		} catch(IOException e) { 
+			moduleStack=null;
+			throw new InputFormatException();
+		}
 		if(!res) throw new InputFormatException();
 		// calculate max time of database
 		for(IWaveform waveform:signals) {
@@ -159,9 +156,8 @@ public class VCDDbLoader implements IWaveformDbLoader, IVCDDatabaseBuilder {
 	@SuppressWarnings("unchecked")
 	@Override
 	public Integer newNet(String name, int i, int width) {
-		String netName = moduleStack.empty()? name: moduleStack.lastElement()+"."+name;
+		String netName = moduleStack.isEmpty()? name: moduleStack.peek()+"."+name;
 		int id = signals.size();
-		assert(width>=0);
 		if(width==0) {
 			signals.add( i<0 ? new VCDSignal<DoubleVal>(db, id, netName, width) :
 				new VCDSignal<DoubleVal>((VCDSignal<DoubleVal>)signals.get(i), id, netName));			

plugins/com.minres.scviewer.database.vcd/src/com/minres/scviewer/database/vcd/VCDFileParser.java

@@ -11,6 +11,7 @@
 package com.minres.scviewer.database.vcd;
 
 import java.io.*;
+import java.text.ParseException;
 import java.util.*;
 
 import com.minres.scviewer.database.BitValue;
@@ -19,7 +20,7 @@ import com.minres.scviewer.database.BitVector;
 class VCDFileParser {
 	private StreamTokenizer tokenizer;
 	private IVCDDatabaseBuilder traceBuilder;
-	private HashMap<String, Integer> nameToNetMap = new HashMap<String, Integer>();
+	private HashMap<String, Integer> nameToNetMap = new HashMap<>();
 	private long picoSecondsPerIncrement;
 	private boolean stripNetWidth;
 	private boolean replaceColon;
@@ -50,19 +51,19 @@ class VCDFileParser {
 		}
 	}
 
-	private void parseScope() throws Exception {
+	private void parseScope() throws IOException, ParseException {
 		nextToken(); // Scope type (ignore)
 		nextToken();
 		traceBuilder.enterModule(tokenizer.sval);
 		match("$end");
 	}
 
-	private void parseUpscope() throws Exception {
+	private void parseUpscope() throws IOException, ParseException {
 		match("$end");
 		traceBuilder.exitModule();
 	}
 
-	private void parseVar() throws Exception {
+	private void parseVar() throws IOException {
 		nextToken(); // type
 		String type = tokenizer.sval;
 		nextToken(); // size
@@ -72,11 +73,12 @@ class VCDFileParser {
 		nextToken();
 		String id = tokenizer.sval;
 		nextToken();
-		String netName = tokenizer.sval;
+		StringBuilder sb = new StringBuilder();
+		sb.append(tokenizer.sval);
 		while (nextToken() && !tokenizer.sval.equals("$end")) {
-			netName+=tokenizer.sval;
+			sb.append(tokenizer.sval);
 		}
-
+		String netName = sb.toString();
 		Integer net = nameToNetMap.get(id);
 		if (net == null) { // We've never seen this net before
 			int openBracket = netName.indexOf('[');
@@ -86,9 +88,9 @@ class VCDFileParser {
 			}
 			if(replaceColon) {
 				if (openBracket != -1) {
-					netName = netName.substring(0, openBracket).replaceAll(":", ".")+netName.substring(openBracket);
+					netName = netName.substring(0, openBracket).replace(":", ".")+netName.substring(openBracket);
 				} else
-					netName=netName.replaceAll(":", ".");
+					netName=netName.replace(":", ".");
 			}
 			nameToNetMap.put(id, traceBuilder.newNet(netName, -1, width));
 		} else {
@@ -97,25 +99,28 @@ class VCDFileParser {
 		}
 	}
 
-	private void parseComment() throws Exception {
+	private void parseComment() throws IOException {
 		nextToken();
-		String s = tokenizer.sval;
+		StringBuilder s = new StringBuilder();
+		s.append(tokenizer.sval);
 		nextToken();
 		while(!tokenizer.sval.equals("$end")){
-			s+=" "+tokenizer.sval;
+			s.append(" ").append(tokenizer.sval);
 			nextToken();
 		}
-		replaceColon|=s.contains("ARTERIS Architecture");
+		replaceColon|=s.toString().contains("ARTERIS Architecture");
 	}
 
-	private void parseTimescale() throws Exception {
+	private void parseTimescale() throws IOException {
 		nextToken();
-		String s = tokenizer.sval;
+		StringBuilder sb = new StringBuilder();
+		sb.append(tokenizer.sval);
 		nextToken();
 		while(!tokenizer.sval.equals("$end")){
-			s+=" "+tokenizer.sval;
+			sb.append(" ").append(tokenizer.sval);
 			nextToken();
 		}
+		String s = sb.toString();
 		switch (s.charAt(s.length() - 2)){
 		case 'p': // Nano-seconds
 			picoSecondsPerIncrement = 1;
@@ -141,7 +146,7 @@ class VCDFileParser {
 		picoSecondsPerIncrement *= Long.parseLong(s);
 	}
 
-	private boolean parseDefinition() throws Exception {
+	private boolean parseDefinition() throws IOException, ParseException {
 		nextToken();
 		if (tokenizer.sval.equals("$scope"))
 			parseScope();
@@ -166,7 +171,7 @@ class VCDFileParser {
 		return true;
 	}
 
-	private boolean parseTransition() throws Exception {
+	private boolean parseTransition() throws IOException {
 		if (!nextToken()) return false;
 		if (tokenizer.sval.charAt(0) == '#') {	// If the line begins with a #, this is a timestamp.
 			currentTime = Long.parseLong(tokenizer.sval.substring(1)) * picoSecondsPerIncrement;
@@ -179,16 +184,10 @@ class VCDFileParser {
 			}
 			if (tokenizer.sval.equals("$dumpvars") || tokenizer.sval.equals("$end"))
 				return true;
-			String value, id;
+			String value;
-			if (tokenizer.sval.charAt(0) == 'b') {
+			String id;
-				// Multiple value net. Value appears first, followed by space,
+			if (tokenizer.sval.charAt(0) == 'b' || tokenizer.sval.charAt(0) == 'r') {
-				// then identifier
+				// Multiple value net. Value appears first, followed by space, then identifier
-				value = tokenizer.sval.substring(1);
-				nextToken();
-				id = tokenizer.sval;
-			}else if (tokenizer.sval.charAt(0) == 'r') {
-					// Multiple value net. Value appears first, followed by space,
-					// then identifier
 				value = tokenizer.sval.substring(1);
 				nextToken();
 				id = tokenizer.sval;
@@ -199,10 +198,8 @@ class VCDFileParser {
 			}
 
 			Integer net = nameToNetMap.get(id);
-			if (net == null) {
+			if (net == null) 
-				System.out.println("unknown net " + id + " value " + value);
 				return true;
-			}
 
 			int netWidth = traceBuilder.getNetWidth(net);
 			if(netWidth==0) {
@@ -253,14 +250,14 @@ class VCDFileParser {
 		return true;
 	}
 
-	private void match(String value) throws Exception {
+	private void match(String value) throws ParseException, IOException {
 		nextToken();
 		if (!tokenizer.sval.equals(value)) 
-			throw new Exception("Line "+tokenizer.lineno()+": parse error, expected "+value+" got "+tokenizer.sval);
+			throw new ParseException("Line "+tokenizer.lineno()+": parse error, expected "+value+" got "+tokenizer.sval, tokenizer.lineno());
 	}
 
 	private boolean nextToken() throws IOException {
 		return tokenizer.nextToken() != StreamTokenizer.TT_EOF;
 	}
 
-};
+}

plugins/com.minres.scviewer.database.vcd/src/com/minres/scviewer/database/vcd/VCDSignal.java

@@ -46,18 +46,16 @@ public class VCDSignal<T extends IEvent> extends HierNode implements IWaveform {
 		fullName=name;
 		this.id=id;
 		this.width=width;
-		this.values=new TreeMap<Long, IEvent[]>();
+		this.values=new TreeMap<>();
 	}
 
-	public VCDSignal(VCDSignal<T> other, int id, String name) {
+	public VCDSignal(VCDSignal<T> o, int id, String name) {
 		super(name);
 		fullName=name;
 		this.id=id;
-		assert(other instanceof VCDSignal<?>);
-		VCDSignal<T> o = (VCDSignal<T>)other;
 		this.width=o.width;
 		this.values=o.values;
-		this.db=other.getDb();
+		this.db=o.getDb();
 	}
 
 	@Override
@@ -105,13 +103,13 @@ public class VCDSignal<T extends IEvent> extends HierNode implements IWaveform {
     public IEvent[] getEventsBeforeTime(Long time) {
     	Entry<Long, IEvent[]> e = values.floorEntry(time);
     	if(e==null)
-    		return null;
+    		return new IEvent[] {};
     	else
     		return values.floorEntry(time).getValue();
     }
 
 	@Override
-	public Boolean equals(IWaveform other) {
+	public boolean isSame(IWaveform other) {
 		return( other instanceof VCDSignal<?> && this.getId().equals(other.getId()));
 	}
 

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/BitVector.java

@@ -76,7 +76,7 @@ public class BitVector implements IEvent {
 		for(int i=resWidth-1; i>=0; i--){
 			int digit=0;
 			for(int j=3; j>=0; j--){
-				if((4*i+j)>=value.length) continue;
+				if((4*i+j)<value.length) {
 					BitValue val = BitValue.fromChar(value[4*i+j]);
 					switch(val) {
 					case X:
@@ -90,6 +90,7 @@ public class BitVector implements IEvent {
 						break;
 					}
 				}
+			}
 			res[i]=Character.forDigit(digit, 16); //((digit < 10) ? '0' + digit : 'a' + digit -10)
 		}
 		return new String(res);		

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/DataType.java

@@ -25,4 +25,4 @@ public enum DataType {
 	POINTER, // T*
 	ARRAY, // T[N]
 	STRING // string, std::string
-};
+}

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/HierNode.java

@@ -26,7 +26,7 @@ public class HierNode implements IHierNode {
 	protected PropertyChangeSupport pcs;
 
 	public HierNode() {
-		childs = new ArrayList<IHierNode>();
+		childs = new ArrayList<>();
 		pcs=new PropertyChangeSupport(this);
 	}
 
@@ -85,4 +85,9 @@ public class HierNode implements IHierNode {
 		return getFullName().compareTo(o.getFullName());
 	}
 
+	@Override
+	public IDerivedWaveform deriveWaveform() {
+		return null;
+	}
+
 }

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/IDerivedWaveform.java

@@ -0,0 +1,19 @@
+/*******************************************************************************
+ * Copyright (c) 2015, 2020 MINRES Technologies GmbH and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     MINRES Technologies GmbH - initial API and implementation
+ *******************************************************************************/
+package com.minres.scviewer.database;
+
+/**
+ * The Interface IDerivedWaveform.
+ */
+public interface IDerivedWaveform extends IWaveform {
+
+	void addSourceWaveform(IWaveform waveform);
+}

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/IHierNode.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2015 MINRES Technologies GmbH and others.
+ * Copyright (c) 2015, 2020 MINRES Technologies GmbH and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -13,6 +13,9 @@ package com.minres.scviewer.database;
 import java.beans.PropertyChangeListener;
 import java.util.List;
 
+/**
+ * The Interface IHierNode.
+ */
 public interface IHierNode extends Comparable<IHierNode>{
 	
 	/**
@@ -33,14 +36,46 @@ public interface IHierNode extends Comparable<IHierNode>{
 	 */
 	public void removePropertyChangeListener(PropertyChangeListener l) ;
 
+	/**
+	 * Gets the full name.
+	 *
+	 * @return the full name
+	 */
 	public String getFullName();
 	
+	/**
+	 * Gets the name.
+	 *
+	 * @return the name
+	 */
 	public String getName();
 	
+	/**
+	 * Sets the name.
+	 *
+	 * @param name the new name
+	 */
 	public void setName(String name);
 	
+	/**
+	 * Sets the parent.
+	 *
+	 * @param parent the new parent
+	 */
 	public void setParent(IHierNode parent);
 
+	/**
+	 * Gets the child nodes.
+	 *
+	 * @return the child nodes
+	 */
 	public List<IHierNode> getChildNodes();
 	
+	/**
+	 * Derive waveform.
+	 *
+	 * @return the i derived waveform or null if none could be created
+	 */
+	public IDerivedWaveform deriveWaveform();
+
 }

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/IWaveform.java

@@ -18,7 +18,7 @@ public interface IWaveform extends IHierNode {
 
 	public IWaveformDb getDb();
 	
-	public Boolean equals(IWaveform other);
+	public boolean isSame(IWaveform other);
 
 	public NavigableMap<Long, IEvent[]> getEvents();
 

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/IWaveformDbLoader.java

@@ -15,7 +15,7 @@ import java.util.Collection;
 
 public interface IWaveformDbLoader {
 	
-	public boolean load(IWaveformDb db, File inp) throws Exception;
+	public boolean load(IWaveformDb db, File inp) throws InputFormatException;
 	
 	public Long getMaxTime();
 	

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/RelationType.java

@@ -50,4 +50,9 @@ public class RelationType {
 	public int hashCode() {
 		return name.hashCode();
 	}
+	
+	@Override
+	public boolean equals(Object obj) {
+		return name.equals(obj);
+	}
 }

plugins/com.minres.scviewer.database/src/com/minres/scviewer/database/internal/WaveformDb.java

@@ -13,7 +13,6 @@ package com.minres.scviewer.database.internal;
 import java.io.File;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.Comparator;
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.List;
@@ -24,12 +23,11 @@ import com.minres.scviewer.database.IHierNode;
 import com.minres.scviewer.database.IWaveform;
 import com.minres.scviewer.database.IWaveformDb;
 import com.minres.scviewer.database.IWaveformDbLoader;
-import com.minres.scviewer.database.InputFormatException;
 import com.minres.scviewer.database.RelationType;
 
 public class WaveformDb extends HierNode implements IWaveformDb {
 
-	private static List<IWaveformDbLoader> loaders=new LinkedList<IWaveformDbLoader>();
+	private static List<IWaveformDbLoader> loaders=new LinkedList<>();
 
 	private boolean loaded;
 
@@ -55,7 +53,7 @@ public class WaveformDb extends HierNode implements IWaveformDb {
 
 	public WaveformDb() {
 		super();
-		waveforms = new HashMap<String, IWaveform>();
+		waveforms = new HashMap<>();
 		relationTypes=new ArrayList<>();
 		maxTime=0L;
 	}
@@ -72,7 +70,7 @@ public class WaveformDb extends HierNode implements IWaveformDb {
 
 	@Override
 	public List<IWaveform> getAllWaves() {
-		return new ArrayList<IWaveform>(waveforms.values());
+		return new ArrayList<>(waveforms.values());
 	}
 
 	@Override
@@ -121,9 +119,8 @@ public class WaveformDb extends HierNode implements IWaveformDb {
 		return loaded;
 	}
 
-	private void buildHierarchyNodes() throws InputFormatException{
+	private void buildHierarchyNodes() {
 		for(IWaveform stream:getAllWaves()){
-			//updateMaxTime(stream);
 			String[] hier = stream.getName().split("\\.");
 			IHierNode node = this;
 			for(int i=0; i<hier.length-1; ++i){
@@ -152,14 +149,9 @@ public class WaveformDb extends HierNode implements IWaveformDb {
 	}
 
 	private void sortRecursive(IHierNode node) {
-		Collections.sort(node.getChildNodes(), new Comparator<IHierNode>() {
+		Collections.sort(node.getChildNodes(), (IHierNode o1, IHierNode o2) -> o1.getName().compareTo(o2.getName()));
-			@Override
-			public int compare(IHierNode o1, IHierNode o2) {
-				return o1.getName().compareTo(o2.getName());			}
-			
-		});
 		for(IHierNode n:node.getChildNodes()) {
-			if(n.getChildNodes().size()>0)
+			if(!n.getChildNodes().isEmpty())
 				sortRecursive(n);
 		}
 	}

plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/parts/LoadingWaveformDb.java

@@ -5,6 +5,7 @@ import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
 
+import com.minres.scviewer.database.IDerivedWaveform;
 import com.minres.scviewer.database.IHierNode;
 import com.minres.scviewer.database.IWaveform;
 import com.minres.scviewer.database.IWaveformDb;
@@ -85,4 +86,9 @@ public class LoadingWaveformDb implements IWaveformDb {
 	public void clear() {
 	}
 
+	@Override
+	public IDerivedWaveform deriveWaveform() {
+		return null;
+	}
+
 }