i already able to print text using kotlin to thermal printer, but im still dont know how to print image to thermal printer in kotlin. please give me sample printing image to thermal printer in kotlin.i already search for the topics, but it written in java, i doesnt know java very much thanks for the help
private fun p1() {
val namaToko = "Rose Medical"
val alamatToko = "Pramuka raya no.1 Jakarta Timur"
val telp = "021-85901642"
val enter = "\n"
val strip = "-"
val rp ="Rp."
val ex = " X "
val textTotal = "Total Rp:"
val ppnTv = "PPN :Rp."
val chargeTv ="Charge :Rp."
val totalTv = "Total Belanja :Rp."
val scope = CoroutineScope(Dispatchers.IO)
scope.launch {
// chunks1
try{
writeWithFormat(namaToko.toByteArray(),Formatter().get(),Formatter.centerAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(alamatToko.toByteArray(),Formatter().get(),Formatter.centerAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(telp.toByteArray(),Formatter().get(),Formatter.centerAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
}catch (e: Exception) {
Log.e("PrintActivity", "Exe ", e)
}
// chunks2
for(pointer in salesBody.indices){
try {
val merk = salesBody[pointer].merk
writeWithFormat(merk!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(strip.toByteArray(),Formatter().get(),Formatter.leftAlign())
val barang = salesBody[pointer].namaBrg
writeWithFormat(barang!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
val varian = salesBody[pointer].varian
writeWithFormat(varian!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(rp.toByteArray(),Formatter().get(),Formatter.leftAlign())
val harga = ValidNumber().deciformat(salesBody[pointer].hargaJual.toString())
writeWithFormat(harga.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(ex.toByteArray(),Formatter().get(),Formatter.leftAlign())
val jumlah = ValidNumber().deciformat(salesBody[pointer].qty.toString())
writeWithFormat(jumlah.toByteArray(),Formatter().get(),Formatter.leftAlign())
val satuan = salesBody[pointer].unit
writeWithFormat(satuan!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(textTotal.toByteArray(),Formatter().get(),Formatter.rightAlign())
val total = ValidNumber().deciformat(salesBody[pointer].total.toString())
writeWithFormat(total.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
}catch (e: Exception) {
Log.e("PrintActivity", "Exe ", e)
}
}
// chunks3
try{
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
val tanggal = salesHeader[0].tanggal
writeWithFormat(tanggal!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(strip.toByteArray(),Formatter().get(),Formatter.leftAlign())
val jam = salesHeader[0].jam
writeWithFormat(jam!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(strip.toByteArray(),Formatter().get(),Formatter.leftAlign())
val idTag= salesHeader[0].idTag
writeWithFormat(idTag!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
val payment= salesHeader[0].payment
writeWithFormat(payment!!.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.leftAlign())
writeWithFormat(ppnTv.toByteArray(),Formatter().get(),Formatter.rightAlign())
val ppnValue = ValidNumber().deciformat(salesHeader[0].ppn.toString())
writeWithFormat(ppnValue.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(chargeTv.toByteArray(),Formatter().get(),Formatter.rightAlign())
val chargeValue = ValidNumber().deciformat(salesHeader[0].charge.toString())
writeWithFormat(chargeValue.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(totalTv.toByteArray(),Formatter().get(),Formatter.rightAlign())
var totalValue = ValidNumber().deciformat(salesHeader[0].allTotal.toString())
writeWithFormat(totalValue.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
writeWithFormat(enter.toByteArray(),Formatter().get(),Formatter.rightAlign())
}catch (e: Exception) {
Log.e("PrintActivity", "Exe ", e)
}
}
}
//print code
class Formatter {
/** The format that is being build on */
private val mFormat: ByteArray
init {
// Default:
mFormat = byteArrayOf(27, 33, 0)
}
/**
* Method to get the Build result
*
* #return the format
*/
fun get(): ByteArray {
return mFormat
}
fun bold(): Formatter {
// Apply bold:
mFormat[2] = (0x8 or mFormat[2].toInt()).toByte()
return this
}
fun small(): Formatter {
mFormat[2] = (0x1 or mFormat[2].toInt()).toByte()
return this
}
fun height(): Formatter {
mFormat[2] = (0x10 or mFormat[2].toInt()).toByte()
return this
}
fun width(): Formatter {
mFormat[2] = (0x20 or mFormat[2].toInt()).toByte()
return this
}
fun underlined(): Formatter {
mFormat[2] = (0x80 or mFormat[2].toInt()).toByte()
return this
}
companion object {
fun rightAlign(): ByteArray {
return byteArrayOf(0x1B, 'a'.code.toByte(), 0x02)
}
fun leftAlign(): ByteArray {
return byteArrayOf(0x1B, 'a'.code.toByte(), 0x00)
}
fun centerAlign(): ByteArray {
return byteArrayOf(0x1B, 'a'.code.toByte(), 0x01)
}
}
}//last
fun writeWithFormat(buffer: ByteArray, pFormat: ByteArray?, pAlignment: ByteArray?): Boolean {
val mmOutStream: OutputStream = mBluetoothSocket.outputStream
return try {
// Notify printer it should be printed with given alignment:
mmOutStream.write(pAlignment)
// Notify printer it should be printed in the given format:
mmOutStream.write(pFormat)
// Write the actual data:
mmOutStream.write(buffer, 0, buffer.size)
// Share the sent message back to the UI Activity
//App.getInstance().getHandler().obtainMessage(MESSAGE_WRITE, buffer.size, -1, buffer).sendToTarget()
true
} catch (e: IOException) {
Log.e(TAG, "Exception during write", e)
false
}
}
//print code close
Using Thermal Printer repo references, I managed to print image to Bluetooth thermal printer. Make sure to use a proper black and white image to print.
Here is the piece of code I used to make a java class
--BitmapHelper.java.
public class BitmapHelper {
private static String[] binaryArray = { "0000", "0001", "0010", "0011",
"0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011",
"1100", "1101", "1110", "1111" };
public static byte[] decodeBitmap(Bitmap bmp){
//Bitmap bmp = Bitmap.createScaledBitmap(bitmap, 50, 50, false);
int maxWidth = 350;
int bmpWidth = bmp.getWidth();
int bmpHeight = bmp.getHeight();
if(bmpWidth > maxWidth){
float aspectRatio = bmp.getWidth() /
(float) bmp.getHeight();
bmpWidth = maxWidth;
bmpHeight = Math.round(bmpWidth / aspectRatio);
bmp = Bitmap.createScaledBitmap(bmp, bmpWidth, bmpHeight, false);
}
List<String> list = new ArrayList<>(); //binaryString list
StringBuffer sb;
int zeroCount = bmpWidth % 8;
StringBuilder zeroStr = new StringBuilder();
if (zeroCount > 0) {
for (int i = 0; i < (8 - zeroCount); i++) {
zeroStr.append("0");
}
}
for (int i = 0; i < bmpHeight; i++) {
sb = new StringBuffer();
for (int j = 0; j < bmpWidth; j++) {
int color = bmp.getPixel(j, i);
int r = (color >> 16) & 0xff;
int g = (color >> 8) & 0xff;
int b = color & 0xff;
// if color close to white，bit='0', else bit='1'
if (r > 160 && g > 160 && b > 160)
sb.append("0");
else
sb.append("1");
}
if (zeroCount > 0) {
sb.append(zeroStr);
}
list.add(sb.toString());
}
List<String> bmpHexList = binaryListToHexStringList(list);
String commandHexString = "1D763000";
String widthHexString = Integer
.toHexString(bmpWidth % 8 == 0 ? bmpWidth / 8
: (bmpWidth / 8 + 1));
if (widthHexString.length() > 2) {
Log.e("decodeBitmap error", " width is too large");
return null;
} else if (widthHexString.length() == 1) {
widthHexString = "0" + widthHexString;
}
widthHexString = widthHexString + "00";
String heightHexString = Integer.toHexString(bmpHeight);
if (heightHexString.length() > 2) {
Log.e("decodeBitmap error", " height is too large");
return null;
} else if (heightHexString.length() == 1) {
heightHexString = "0" + heightHexString;
}
heightHexString = heightHexString + "00";
List<String> commandList = new ArrayList<>();
commandList.add(commandHexString+widthHexString+heightHexString);
commandList.addAll(bmpHexList);
return hexList2Byte(commandList);
}
private static List<String> binaryListToHexStringList(List<String> list) {
List<String> hexList = new ArrayList<String>();
for (String binaryStr : list) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < binaryStr.length(); i += 8) {
String str = binaryStr.substring(i, i + 8);
String hexString = myBinaryStrToHexString(str);
sb.append(hexString);
}
hexList.add(sb.toString());
}
return hexList;
}
private static String myBinaryStrToHexString(String binaryStr) {
StringBuilder hex = new StringBuilder();
String f4 = binaryStr.substring(0, 4);
String b4 = binaryStr.substring(4, 8);
String hexStr = "0123456789ABCDEF";
for (int i = 0; i < binaryArray.length; i++) {
if (f4.equals(binaryArray[i]))
hex.append(hexStr.substring(i, i + 1));
}
for (int i = 0; i < binaryArray.length; i++) {
if (b4.equals(binaryArray[i]))
hex.append(hexStr.substring(i, i + 1));
}
return hex.toString();
}
private static byte[] hexList2Byte(List<String> list) {
List<byte[]> commandList = new ArrayList<byte[]>();
for (String hexStr : list) {
commandList.add(hexStringToBytes(hexStr));
}
return sysCopy(commandList);
}
private static byte[] hexStringToBytes(String hexString) {
if (hexString == null || hexString.equals("")) {
return null;
}
hexString = hexString.toUpperCase();
int length = hexString.length() / 2;
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = 0; i < length; i++) {
int pos = i * 2;
d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
}
return d;
}
private static byte[] sysCopy(List<byte[]> srcArrays) {
int len = 0;
for (byte[] srcArray : srcArrays) {
len += srcArray.length;
}
byte[] destArray = new byte[len];
int destLen = 0;
for (byte[] srcArray : srcArrays) {
System.arraycopy(srcArray, 0, destArray, destLen, srcArray.length);
destLen += srcArray.length;
}
return destArray;
}
private static byte charToByte(char c) {
return (byte) "0123456789ABCDEF".indexOf(c);
}
}
Then I use it in the print activity:
private fun p2(){
val convertBmp : Bitmap
convertBmp = BitmapFactory.decodeResource(getResources(),com.example.ronibluetooth.R.drawable.poly)
val decodeBmp = BitmapHelper.decodeBitmap(convertBmp)
val scope = CoroutineScope(Dispatchers.IO)
scope.launch {
try {
val os =mBluetoothSocket.outputStream
os.write(decodeBmp,0,decodeBmp.size)
}
catch (e: Exception) {
Log.e("PrintActivity", "Exe ", e)
}
}
}
image to print
result print
I wrote this code to ask user for inputting one of the values in the enumeration but I don't know how to connect the enumeration values to the user input. Please help.
Thank you!
class Program
{
static void Main(string[] args)
{
System.Console.WriteLine("Hello, please enter the numerical value corresponding to your transportation mode.Car = 10 / Bus = 20 / Bicycle = 5 / Cab = 7.");
int TransportationModeInput = int.Parse(Console.ReadLine());
public enum TransporationMode
{
Car = 10,
Bus = 20,
Bicycle = 5,
Cab = 7
}
int ModeCar = (int)TransporationMode.Car;
int ModeBus = (int)TransporationMode.Bus;
int ModeBicycle = (int)TransporationMode.Bicycle;
int ModeCab = (int)TransporationMode.Cab;
}
}
(TransporationMode)TransportationModeInput It Auto Casting to enum
public enum TransporationMode
{
Car = 10,
Bus = 20,
Bicycle = 5,
Cab = 7
}
class Program
{
static void Main(string[] args)
{
System.Console.WriteLine("Hello, please enter the numerical value corresponding to your transportation mode.Car = 10 / Bus = 20 / Bicycle = 5 / Cab = 7.");
int TransportationModeInput = int.Parse(Console.ReadLine());
Console.WriteLine("Answer:" + ((TransporationMode)TransportationModeInput).ToString());
Console.ReadLine();
}
}
there's one Object
#Data
class ScoreInfo{
String id;
float cove_score;
float theam_score;
float content_score;
float teach_score;
Date create_date;
ScoreInfoP scoreInfoP;
}
and ScoreInfoP is :
#Data
class ScoreInfoP{
String stream_sn;
String anchor_id;
String create_by;
}
sourceList is a list of ScoreInfo,I want to get cove_score,theam_score,content_score,teach_score's mean values,group by scoreInfoP property and return four mean values for each of these properties.
I can get only one mean value using such code:
Map<ScoreInfoP, Double> meanForCoveScore = sourceList.stream().collect(Collectors.groupingBy(ScoreInfo::getScoreInfoP,
Collectors.averagingDouble(ScoreInfo::getCove_score)));
I want to learn how to get four mean values using java8 or any easier way you suggest achieving this.
Waiting here for your generous help.
There isn't anything build-in for this, but it's not that complicated to build a custom Collector for that...
Map<String, List<Float>> result = Arrays.asList(first, second)
.stream()
.collect(Collectors.groupingBy(
x -> x.getScoreInfoP().getAnchorId(),
Collector.of(
() -> new float[5],
(a, x) -> {
a[0] += x.getCoveScore();
a[1] += x.getTheamScore();
a[2] += x.getTeachScore();
a[3] += x.getContentScore();
a[4]++;
},
(left, right) -> {
for (int i = 0; i < 4; ++i) {
left[i] += right[i];
}
return left;
}, x -> Arrays.asList(x[0] / x[4], x[1] / x[4], x[2] / x[4], x[3] / x[4]))
));
System.out.println(result);
I actually groupBy here on ScoreInfoP#anchorId; but you can do it on ScoreInfoP - for that you need to change x -> x.getScoreInfoP().getAnchorId() to x -> x.getScoreInfoP(). But obviously ScoreInfoP needs to override hashCode and equals.
As I said in the comment you should use a proper result class.
class ScoreInfoAverage {
private float cove_score;
private float theam_score;
private float content_score;
private float teach_score;
// ctor, getter, setter
}
Then you can use a custom Collector:
public static Collector<ScoreInfo, ?, ScoreInfoAverage> scoreInfoToAverage() {
class ScoreInfoAccumulator {
private DoubleSummaryStatistics cove_score = new DoubleSummaryStatistics();
private DoubleSummaryStatistics theam_score = new DoubleSummaryStatistics();
private DoubleSummaryStatistics content_score = new DoubleSummaryStatistics();
private DoubleSummaryStatistics teach_score = new DoubleSummaryStatistics();
public void add(ScoreInfo si) {
cove_score.accept(si.cove_score);
theam_score.accept(si.theam_score);
content_score.accept(si.content_score);
teach_score.accept(si.teach_score);
}
public ScoreInfoAccumulator combine(ScoreInfoAccumulator sia) {
cove_score.combine(sia.cove_score);
theam_score.combine(sia.theam_score);
content_score.combine(sia.content_score);
teach_score.combine(sia.teach_score);
return this;
}
public ScoreInfoAverage average() {
return new ScoreInfoAverage((float) cove_score.getAverage(),
(float) theam_score.getAverage(), (float) content_score.getAverage(),
(float) teach_score.getAverage());
}
}
return Collector.of(ScoreInfoAccumulator::new, ScoreInfoAccumulator::add,
ScoreInfoAccumulator::combine, ScoreInfoAccumulator::average);
}
Last but not least you add your Collector to the downstream:
Map<ScoreInfoP, ScoreInfoAverage> collect = scoreInfos.stream()
.collect(Collectors.groupingBy(ScoreInfo::getScoreInfoP, scoreInfoToAverage()));
I am working on an algorithm and it seems to be working fine, apart from one thing.
Let me first show you the code and then I will explain what the code does and what the problem is.
public Triple<List<ROUTE>, Integer, List<Customer>> LocalSearch()
{
int noImprLS = 0;
boolean initialization = false;
List<ROUTE> bestRoutes = startRoutes;
int bestProfit = profit;
List<Customer> bestU = u;
List<ROUTE> tempBestRoutes = startRoutes;
int tempBestProfit = profit;
List<Customer> tempBestU = u;
int tempBestDistance = totalDistance(tempBestRoutes);
ELIMINATOR e = new ELIMINATOR(bestU, bestRoutes, bestProfit, initialization, name, rnd);
while (noImprLS <= noImprUB)
{
System.out.print(noImprLS);
boolean improvement = false;
long starttime = System.nanoTime();
double timeE = 0;
for (int i = 1; i <= N; i++)
{
long starttimeE = System.nanoTime();
e = new ELIMINATOR(bestU, bestRoutes, bestProfit, initialization, name, rnd);
timeE = timeE + (System.nanoTime()-starttimeE)/1000000000.0;
POSTPROCEDURE pp = new POSTPROCEDURE(e.getRoutes(), profitRoutes(e.getRoutes()), e.getU(), name);
for (int p = 0; p < pp.getBestSolution().size(); p++)
{
ROUTE r = pp.getBestSolution().get(p);
addToPOOL(r);
}
int tempprofit = pp.getTP();
int tempdistance = pp.getTD();
if (tempprofit > tempBestProfit)
{
tempBestRoutes = pp.getBestSolution();
tempBestProfit = tempprofit;
tempBestU = pp.getU();
tempBestDistance = tempdistance;
}
else if (tempprofit == tempBestProfit)
{
if (tempdistance < tempBestDistance)
{
tempBestRoutes = pp.getBestSolution();
tempBestProfit = tempprofit;
tempBestU = pp.getU();
tempBestDistance = tempdistance;
}
}
}
if (tempBestProfit > bestProfit)
{
// Move to better neighbor
bestRoutes = tempBestRoutes;
bestProfit = tempBestProfit;
bestU = tempBestU;
noImprLS = 0;
improvement = true;
System.out.print(" total profit: " + bestProfit);
}
else if (tempBestProfit == bestProfit)
{
if (totalDistance(tempBestRoutes) < totalDistance(bestRoutes))
{
// Move to better neighbor
bestRoutes = tempBestRoutes;
bestProfit = tempBestProfit;
bestU = tempBestU;
noImprLS = 0;
improvement = true;
System.out.print(" total profit: " + bestProfit + " total distance: " + totalDistance(bestRoutes));
}
}
if (improvement == false)
{
noImprLS++;
}
long endtime = System.nanoTime();
double duration = (endtime - starttime)/1000000000.0;
System.out.print(" duration: " + duration + " timeE: " + timeE + "\n");
}
Explanation
I know that the code is quite lengthy, but it is all quite important. In this code, I am writing an algorithm for the Team Orienteering Problem with Time Windows (extensive case of the Vehicle Routing Problems). My aim is to find a good set of routes with maximum profit. In the example below, bestRoutes and tempBestRoutes consist of 4 different routes, profit (bestProfit/tempBestProfit) is equal to the total profit of these routes respectively, and (temp)bestU is a list of customers that are not included in my route yet.
The problem now is with ELIMINATOR. This method removes and adds some customers. The output of this class is used for PostProcedure that also changes some facts in the routes.
I hope it is kind of clear now what my code is doing. I am considering N neighbourhoods and I will choose the best one. If the best one is not better than my starting solution, I increase noImprLS with one. I keep on considering new nieghbours until my upperbound on the number of consecutive iterations without improvement is met.
Problem
The problem now is that if I have not found a better solution, and hence I keep on inserting the same routes and profit in ELIMINATOR, my computation time increases.
A few examples where duration indicates how long an iteration within the while loop takes, and timeE indicates what the total time of ELIMINATOR in the for loop is. It is clear that ELIMINATOR causees the duration to increase.
0 total profit: 800 duration: 0.486570471 timeE: 0.16644330999999998
0 total profit: 900 duration: 0.431213528 timeE: 0.11342619799999998
0 total profit: 950 duration: 0.444671005 timeE: 0.12090608200000001
0 total profit: 960 duration: 0.519406695 timeE: 0.16836757300000005
0 duration: 0.460473438 timeE: 0.137813155
1 duration: 0.572109775 timeE: 0.30774360900000003
2 duration: 0.698965292 timeE: 0.471859029
3 duration: 0.918376211 timeE: 0.686916669
4 duration: 1.165481175 timeE: 0.92621492
5 duration: 1.326080436 timeE: 1.0874366910000002
6 duration: 2.006102605 timeE: 1.674879135
7 duration: 2.787172112 timeE: 2.4276636639999993
8 duration: 2.042213493 timeE: 1.7967797849999998
9 duration: 2.652985618 timeE: 2.3503671230000003
10 duration: 2.422183993 timeE: 2.1859969810000006
The ELIMINATOR CODE:
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
public class ELIMINATOR extends BASIS
{
private List<Customer> u;
private List<ROUTE> routes;
private int totalprofit;
private Random prob;
public ELIMINATOR(List<Customer> u, List<ROUTE> routes, int profit, boolean initialization, String name, Random rnd)
{
super(name);
this.u = u;
this.routes = routes;
this.totalprofit = profit;
this.prob = rnd;
if (initialization == true)
{
addCustomers();
for (ROUTE route : routes)
{
checkCorrectNess(route, "after adding procedure in eliminator");
}
}
else
{
removeCustomers();
for (ROUTE route : routes)
{
checkCorrectNess(route, "after removing procedure in eliminator");
}
addCustomers();
for (ROUTE route : routes)
{
checkCorrectNess(route, "after removing and adding procedure in eliminator");
}
}
}
public void removeCustomers()
{
double Ph = 0.1;
double Pl = 0.3;
double total_profit = totalprofit;
int num_customers = 0;
// Calculate the total profit and total number of customers in the routes
for(ROUTE route : routes)
{
num_customers = num_customers + (route.getLocations().size()-2);
}
// Calculate average profit
double average_profit = total_profit/num_customers;
// For each customer on each route, determine whether he/she will be removed
for(ROUTE r : routes)
{
List<RouteNode> route = r.getLocations();
int routesize = route.size();
int j = 1;
while (j < routesize-1)
{
boolean removed = false;
RouteNode node = route.get(j);
if (node.customer.getProfit() >= average_profit)
{
if (prob.nextDouble() < Ph)
{
removed = true;
RouteNode node_toberemoved = node;
int index_node = route.indexOf(node);
route.remove(index_node);
u.add(node.customer);
route = removal(route, node_toberemoved, index_node);
r.setLocations(route);
r.setDistance(distanceOneRoute(route));
r.setProfit(profitOneRoute(route));
checkCorrectNess(r, "remove customers eliminator");
}
}
else
{
if (prob.nextDouble() < Pl)
{
removed = true;
RouteNode node_toberemoved = node;
int index_node = route.indexOf(node);
route.remove(index_node);
u.add(node.customer);
route = removal(route, node_toberemoved, index_node);
r.setLocations(route);
r.setDistance(distanceOneRoute(route));
r.setProfit(profitOneRoute(route));
checkCorrectNess(r, "remove customers eliminator");
}
}
if (removed == false)
{
j++;
}
else
{
routesize = route.size();
total_profit = total_profit-node.customer.getProfit();
average_profit = total_profit/num_customers;
}
}
}
totalprofit = profitRoutes(routes);
}
public void addCustomers()
{
List<Customer> u_copy = new ArrayList<Customer>(u);
List<Customer> u_temp = new ArrayList<Customer>(u);
for (Customer c : u_temp)
{
boolean added = false;
for (ROUTE r : routes)
{
checkCorrectNess(r, "add customers eliminator");
if (added == true)
{
break;
}
Customer customer = c;
u_copy.remove(c);
List<RouteNode> route = r.getLocations();
for (int i = 0; i < route.size()-1; i++)
{
RouteNode possibleNode = new RouteNode();
possibleNode.customer = customer;
List<Integer> distances = calculateDistances(route.get(i), possibleNode, route.get(i+1));
// Calculate shift for customer under consideration
int arrivalTime = route.get(i).timeStartService+ route.get(i).customer.getService() + distances.get(0);
int wait = Math.max(0, customer.getOpeningTW()-arrivalTime);
int serviceDuration = customer.getService();
int shift = distances.get(0) + wait + serviceDuration + distances.get(2) - distances.get(1);
// Determine Start Service
int startServiceTime = Math.max(customer.getOpeningTW(), arrivalTime);
// Obtain waiting time of next customer
int waiting_next = route.get(i+1).wait;
// Obtain MaxShift of next customer
int maxShift = route.get(i+1).maxShift;
if (shift <= (waiting_next + maxShift) & startServiceTime <= customer.getClosingTW() )
{
// Customer can be inserted
added = true;
RouteNode newNode = new RouteNode();
newNode.customer = customer;
newNode.arrivalTime = arrivalTime;
newNode.timeStartService = startServiceTime;
newNode.shift = shift;
newNode.wait = wait;
int pos_insertion = i + 1;
route = ADD(route, newNode, pos_insertion);
r.setLocations(route);
r.setDistance(distanceOneRoute(route));
r.setProfit(profitOneRoute(route));
checkCorrectNess(r, "add customers eliminator");
// exit the last for loop
break;
}
}
}
if (added == false)
{
u_copy.add(c);
}
}
u = u_copy;
totalprofit = profitRoutes(routes);
}
/**
* Returns list of unvisited customers
* #return
*/
public List<Customer> getU()
{
return u;
}
/**
* Returns list of routes
* #return
*/
public List<ROUTE> getRoutes()
{
return routes;
}
}
I have a functional interface in Java 8:
public interface IFuncLambda1 {
public int someInt();
}
in main:
IFuncLambda1 iFuncL1 = () -> 5;
System.out.println("\niFuncL1.someInt: " + iFuncL1.someInt());
iFuncL1 = () -> 1;
System.out.println("iFuncL1.someInt: " + iFuncL1.someInt());
Running this will yield:
iFuncL1.someInt: 5
iFuncL1.someInt: 1
Is this functionality OK as it is? Is it intended?
If the overriding would be done in an implementing class, and the implementation would change at some point, then in every place that that method is called, the behaviour would be the same, we would have consistency. But if I change the behaviour/implementation through lambda expressions like in the example, the behaviour will only be valid til the next change, later on in the flow. This feels unreliable and hard to follow.
EDIT:
#assylias I don't see how someInt() has its behaviour changed...
What if I added a param to someInt and have this code:
IFuncLambda1 iFuncL1 = (x) -> x - 1;
System.out.println("\niFuncL1.someInt: " + iFuncL1.someInt(var));
iFuncL1 = (x) -> x + 1;
System.out.println("iFuncL1.someInt: " + iFuncL1.someInt(var));
with var being a final even, how would you re-write that with classes?
In your example, () -> 5 is one object and () -> 1 is another object. You happen to use the same variable to refer to them but that is just how references work in Java.
By the way it behaves exactly the same way as if you had used anonymous classes:
IFuncLambda1 iFuncL1 = new IFuncLambda1() { public int someInt() { return 5; } };
System.out.println("\niFuncL1.someInt: " + iFuncL1.someInt());
iFuncL1 = new IFuncLambda1() { public int someInt() { return 1; } };
System.out.println("iFuncL1.someInt: " + iFuncL1.someInt());
Or using "normal" classes:
public static class A implements IFuncLambda1 {
private final int i;
public A(int i) { this.i = i; }
public int someInt() { return i; }
}
IFuncLambda1 iFuncL1 = new A(5);
System.out.println("\niFuncL1.someInt: " + iFuncL1.someInt());
iFuncL1 = new A(1);
System.out.println("iFuncL1.someInt: " + iFuncL1.someInt());
There again there are two instances of A but you lose the reference to the first instance when you reassign iFuncL1.