Can't see contents of JFrame until I drag open window - java

this is actually my first complete program which will eventually be used to write code for a robot I am making. Everything is working okay, except that when I run it, I have to drag open the window in order to see the content inside it.
Any suggestions on how to fix it.
frame2 - "click to build file" works.
frame - the one with the button grid, is the one I have to drag open to see.
Here is the setup file for frame (the one that doesn't work)
package Grid;
//march 13 to April 11
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import java.awt.*;
import java.awt.event.*;
#SuppressWarnings("serial")
public class ButtonGrid extends JFrame {
public static int clicked[][] = new int[20][40];
static JButton button[] = new JButton[800];
static int x;
static int count = 1;
public static int clickedfinal[][];
int value;
public ButtonGrid() {
JFrame frame = new JFrame();
frame.setSize(400, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
GridLayout grid = new GridLayout(20, 40, 10, 8);
frame.setLayout(grid);
for (int c = 0; c < 20; c++) {
for (int d = 0; d < 40; d++) {
clicked[c][d] = 0;
}
}
for (x = 0; x < 800; x++) {
button[x] = new JButton();
button[x].setActionCommand(Integer.toString(x));
frame.add(button[x]);
button[x].setBackground(Color.LIGHT_GRAY);
button[x].setOpaque(true);
thehandler handler = new thehandler();
button[x].addActionListener(handler);
}
}
public class thehandler implements ActionListener {
public void actionPerformed(ActionEvent e) {
for (;;) {
value = Integer.parseInt(e.getActionCommand());
button[value].setBackground(Color.BLACK);
int r = value % 40;
int m = ((value - (value % 40)) / 40);
// learn how to round up
clicked[m][r] = 1;
break;
}
}
}
public static void main(String[] args) {
new ButtonGrid();
}
}
Here is the file for frame2, the one that does work; To test just run this one.
package Grid;
import javax.swing.JButton;
import javax.swing.JFrame;
import Grid.ButtonGrid;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
#SuppressWarnings("serial")
public class Arduinowriter extends JFrame {
static int t = 1;
static int buttonpressed;
static int total;
static String Code;
static String oldcode;
public Arduinowriter() {
JFrame frame2 = new JFrame("Build File");
JButton button = new JButton("Click to Build File");
frame2.setSize(400, 400);
frame2.add(button);
frame2.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame2.setVisible(true);
button.setActionCommand(Integer.toString(1));
thehandler handler = new thehandler();
button.addActionListener(handler);
}
public class thehandler implements ActionListener {
public void actionPerformed(ActionEvent e) {
buttonpressed = Integer.parseInt(e.getActionCommand());
String newLine = System.getProperty("line.separator");
String Motor2_half = "digitalWrite(Motor2, HIGH);" + newLine
+ "delay(500)" + newLine + "digitalWrite(Motor2, LOW)";
String Motor2_one = "digitalWrite(Motor2, HIGH);" + newLine
+ "delay(1000);" + newLine + "digitalWrite(Motor2, LOW);";
String Servo1_dispense = "digitalWrite(Servo1, HIGH);" + newLine
+ "delay(1000)" + newLine + "digitalWrite(Servo1, LOW);";
String Motor2_back = "digitalWrite(Motor2back, High" + newLine
+ "delay(6000)" + newLine + "digitalWrite(Motor2back, Low)";
String Motor1_forward = "digitalWrite(Motor1, HIGH);" + newLine
+ "delay(1000);" + newLine + "digitalWrite(Motor1, LOW);";
String dispenseCycle = (Motor2_one + newLine + Servo1_dispense
+ " //Domino" + newLine);
String skipCycle = (Motor2_one + newLine);
String backCycle = (Motor1_forward + newLine + Motor2_back + newLine);
while (buttonpressed == 1) {
for (int x = 0; x < 20; x++) {
Code = oldcode + "//Line " + (x + 1);
oldcode = Code;
yloop: for (int y = 0; y < 40; y++) {
boolean empty = true;
for (int check = y; check < 39; check++) {
if (ButtonGrid.clicked[x][check] == 1) {
empty = false;
System.out.println(x + " not empty");
}
}
if (ButtonGrid.clicked[x][y] == 1 && y == 0) {
Code = oldcode + newLine + Servo1_dispense
+ " //Domino" + newLine;
} else if (ButtonGrid.clicked[x][y] == 1) {
Code = oldcode + newLine + dispenseCycle + newLine;
}
else if (ButtonGrid.clicked[x][y] == 0
&& empty == false) {
Code = oldcode + newLine + skipCycle + newLine;
} else {
Code = oldcode + newLine + backCycle + newLine;
oldcode = Code;
break yloop;
}
oldcode = Code;
}
}
try {
BufferedWriter out = new BufferedWriter(new FileWriter(
"C:\\ArduinoCode.txt"));
out.write(Code);
out.close();
} catch (IOException g) {
System.out.println("Exception ");
}
return;
}
}
}
// button
public static void main(String[] args) {
new ButtonGrid();
new Arduinowriter();
}
}
Note: I am a very beginner. This code has taken many many hours to write and I figured everything out using google and youtube. If anything in the code or what I have said is unclear or doesn't make sense, please forgive me and just ask.

Invoke frame.setVisible(true) after you set the layout manager and everything else that affects its "visual" state.

Related

Every time a new swing windows opens in code that is executed in a for loop

Every time a new swing windows opens in code that is executed in a for loop.
I have some code that is runned in a for loop.
The for loop gives every time a new value to my multidimensional array.
But, every time my for loop creates open's a new windows but does not close the old window.
How can I solve this issues? I want to close the old windows and refresh my window with the new actual values or that only one Windows is opened and that the new values of the for loop refreshes the values inside the table based on the multidimensional array names data.
Because now more than 200 (every second a new windows is opened) windows are opened and after 1 minute I don’t see new values appearing on my window and the computer freezes.
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.Timer;
public class UAppWin {
private static final int Status_COL = 1;
String[][] data = new String[3][3];
int dptr;
String[] cols = { "Feature", "Status", "Value" };
public UAppWin(String label, int nphases) {
System.out.println("UApp \"" + label + "\" (" + nphases + " phases)");
}
void newCycle(int phasenr) {
System.out.println("UApp =============================");
dptr = 0;
}
void addEntry(int index, double tim, String label, int status, double dval) {
System.out.println("Uapp [" + index + "] " + label + "(" + status + ") " + dval);
data[dptr][0] = label;
data[dptr][1] = "" + status;
data[dptr][2] = "" + dval;
dptr++;
}
void addMessage(String msg) {
System.out.println("Uapp alert: " + msg);
// rode balk met bericht
}
void deleteMessage() {
}
void endCycle() {
System.out.println("UApp =============================");
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JOptionPane.showMessageDialog(null, new JScrollPane(getNewRenderedTable(getTable())));
}
});
}
private JTable getTable() {
DefaultTableModel model = new DefaultTableModel(data, cols);
return new JTable(model) {
#Override
public Dimension getPreferredScrollableViewportSize() {
return new Dimension(300, 150);
}
};
}
private static JTable getNewRenderedTable(final JTable table) {
table.setDefaultRenderer(Object.class, new DefaultTableCellRenderer() {
#Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected,
boolean hasFocus, int row, int col) {
super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, col);
String Status = (String) table.getModel().getValueAt(row, Status_COL);
if ("0".equals(Status)) {
setBackground(Color.GREEN);
setForeground(Color.BLACK);
} else if ("2".equals(Status)) {
setBackground(Color.RED);
setForeground(Color.BLACK);
} else {
setBackground(Color.YELLOW);
setForeground(Color.BLACK);
}
return this;
}
});
return table;
}
}
The second part of the code edited:
public class HmOpIntf {
static final String DFLT_IP_ADDR = "127.0.0.1";
static final int DFLT_IP_PORT = 9502;
static final int DFLT_MB_UNIT = 1;
static final int DFLT_POLL_TM = 2;
public static ModbusClient connectPLC(String ipAddr, int port, int unitNr)
{
ModbusClient mc = null;
System.out.println("Connecting to " + ipAddr + " port " + port + " unit " + unitNr);
try {
mc = new ModbusClient(ipAddr, port);
mc.Connect();
mc.setUnitIdentifier((byte)unitNr);
mc.WriteSingleCoil(0, true);
} catch (Exception e) {
System.err.println("*** connectPLC: exception caught");
return null;
}
System.out.println("Connected!");
return mc;
}
public static void disconnectPLC(ModbusClient mc)
{
mc = null;
}
public static String MyConvertRegistersToString(int[] regs, int startIx, int len) {
char[] ca = new char[len];
for (int i = 0; i < len; i++) {
ca[i] = (char) regs[startIx + i];
}
return new String(ca);
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
ModbusClient mc = null;
String ipAddr = DFLT_IP_ADDR;
int ipPort = DFLT_IP_PORT;
int mbUnit = DFLT_MB_UNIT;
int pollTime = DFLT_POLL_TM;
int tlBase = 2000; /* Offset in PLC's holding registry */
int tlBlocksz = 84;
String[] tlLabel = {"T4 mould", "T injection valve"}; /* Default */
int trafLightNum = tlLabel.length;
String[] colors = { "green", "yellow", "red" };
int status;
// Notifications.infoBox("Hello world!", "Welcome message");
if (args != null && args.length > 0) {
if (args.length < 4) {
System.err.println("*** Error (" + args.length +"): arguments are: ip-addr port unit polltime label-1 ...");
System.exit(1);
}
ipAddr = args[0];
ipPort = Integer.parseInt(args[1]);
mbUnit = Integer.parseInt(args[2]);
pollTime = Integer.parseInt(args[3]);
}
if (args.length > 4) {
trafLightNum = args.length - 4;
tlLabel = new String[trafLightNum];
for (int i = 0; i < trafLightNum; i++) {
tlLabel[i] = args[i + 4];
}
}
// Scope sc = new Scope();
// sc.runScope();
if ((mc = connectPLC(ipAddr, ipPort, mbUnit)) == null) {
System.out.println("*** Failed to connect to PLC");
System.exit(1);
}
TrafficLight tlLast = null;
int[] values = new int[tlBlocksz];
TrafficLight[] tl = new TrafficLight[trafLightNum];
Scope[] sc = new Scope[trafLightNum];
Notifications nots = new Notifications(trafLightNum);
int locX, locY;
for (int i = 0; i < tl.length; i++) {
tl[i] = new TrafficLight();
tl[i].setLbl(tlLabel[i]);
tl[i].setVisible(true);
if (tlLast != null) {
locX = tlLast.getLocation().x;
locY = tlLast.getLocation().y + tlLast.getHeight();
} else {
locX = tl[i].getLocation().x;
locY = tl[i].getLocation().y;
}
tl[i].setLocation(locX, locY);
sc[i] = new Scope(tlLabel[i], locX + tl[i].getWidth(), locY, 320, 290 /* tl[i].getHeight()-80 */ );
sc[i].setGrid(10, 5);
tlLast = tl[i];
}
UAppWin uw = new UAppWin("RTM Facility", 5);
int phase = 1;
// tl2.setVisible(true); tl2.setLocation(tl.getWidth(), 0);
try {
double t = 0.0;
int[] dreg = new int[2];
for (;;) {
uw.newCycle(phase);
for (int i = 0; i < tl.length; i++) {
values = mc.ReadHoldingRegisters(tlBase + i * tlBlocksz, values.length);
status = values[0];
if (status >= 0 && status < colors.length) {
// System.out.println(i + ": " + colors[status]);
if (status == 0) tl[i].greenOn();
else if (status == 1) tl[i].yellowOn();
else tl[i].redOn();
}
else
System.out.println("Status value " + i + " out of range: " + status);
dreg[0] = values[1]; dreg[1] = values[2];
double dval = (double) ModbusClient.ConvertRegistersToFloat(dreg);
sc[i].addValue(t, dval);
sc[i].drawSignal();
// w.addEntry(int i, float t, String label, int status (o = groen, 1 = yellow, 2 = red), float dval);
uw.addEntry(i, t, tlLabel[i], status, dval);
int msglen = values[3];
if (msglen > 0) {
String msg = MyConvertRegistersToString(values, 4, msglen);
System.out.println("DEBUG: received message for " + tlLabel[i] + ": " + msg);
nots.notify(i, msg);
uw.addMessage(msg);
}
else {
nots.notify(i, null);
uw.deleteMessage();
}
// System.out.println("Received for set " + i + ": status=" + status + " dval=" + dval + " msglen=" + msglen);
}
uw.endCycle();
t += 1.0;
Thread.sleep(pollTime * 500);
}
} catch (Exception e) {
System.out.println("*** Failed to communicate with PLC - exit");
System.exit(1);
}
try {
mc.Disconnect();
} catch (IOException e) {
System.out.println("*** Failed to disconnect from PLC");
}
}
}
The UappWin seems to be tied to a window. So when you create it, also create a JFrame. Then nothing else would need to change except the run method and declaring the JFrame.
public class UAppWin {
private JFrame frame;
public UAppWin(String label, int nphases) {
//System.out.println("UApp \"" + label + "\" (" + nphases + " phases)");
JLabel label = new JLabel("UApp \"" + label + "\" (" + nphases + " phases)");
frame = new JFrame("title");
frame.add(label);
frame.setVisible(true);
}
Then when you create the window.
SwingUtilities.invokeLater(new Runnable() {
public void run() {
//JOptionPane.showMessageDialog(null, new JScrollPane(getNewRenderedTable(getTable())));
frame.setContentPane( new JScrollPane( getNewRenderedTable( getTable() ) );
frame.setVisible(true);
}
});

Why is my class constructor called repeatedly?

Recently I have been working on a program that can convert TeX-generated PDFs to a certain form of text that retains some semantically meaningful style information such as subscripts and superscripts.
When debugging it seems that there might be something very unusual going on with the PDFTextStripper class.
Here is my TeXUtil class that does most of the work.
import com.google.common.base.CharMatcher;
import org.apache.pdfbox.pdmodel.font.PDFont;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.util.Hashtable;
import java.util.Stack;
public class TeXUtil {
private Stack<SSStatus> ssstatus;
private boolean accentMode;
private String fs;
private boolean mathMode;
private SymbolDB db;
private Hashtable<String, String> maccDict;
float endY;//Positions
float endX;
float Y;
int height;//Height
//boolean test;
public TeXUtil() throws IOException {
ssstatus = new Stack<SSStatus>();
fs = "rm";
accentMode = false;//as in the state of being right after an accent
mathMode = false;
db = new SymbolDB();
maccDict = new Hashtable<String, String>();
maccDict.put("\\vec","\\vec");
maccDict.put("\\widehat","\\widehat");
maccDict.put("\\widetilde","\\widetilde");
maccDict.put("\\^","\\hat");
maccDict.put("\\v","\\check");
maccDict.put("\\u","\\breve");
maccDict.put("\\`","\\grave");
maccDict.put("\\~","\\tilde");
maccDict.put("\\=","\\bar");
maccDict.put("\\.","\\dot");
maccDict.put("\\","\\ddot");
maccDict.put("\\'","\\acute");
endY = 0;
endX = 0;
Y = 0;
height = 0;
//test = false;
System.out.println("TeXUtil initialized!");
}
private static String fontShortName(PDFont font) {
String[] segments = font.getName().split("\\+");
return segments[segments.length - 1];
}
private static int fontHeight(PDFont font) {
CharMatcher matcher = CharMatcher.inRange('0', '9');
return Integer.parseInt(matcher.retainFrom(fontShortName(font)));
}
private static String fontClass(PDFont font) {
CharMatcher matcher = CharMatcher.inRange('A', 'Z');
return (matcher.retainFrom(fontShortName(font))).toLowerCase();
}
private String textToTeX(String shortFontName, int code) throws JSONException {
JSONObject info = db.getInfo(shortFontName, code);
return info.getString("value");
}
public String fullTextToTeX(PDFont font, int code, float newEndX, float newY, float newEndY){
String shortFontName = fontClass(font);
try {
JSONObject info = db.getInfo(shortFontName, code);
String teXCode = info.getString("value");
StringBuilder preamble1 = new StringBuilder("");
StringBuilder preamble2 = new StringBuilder("");
StringBuilder postamble = new StringBuilder("");
boolean text = info.getBoolean("text");
boolean math = info.getBoolean("math");
boolean tacc = info.getBoolean("tacc");
boolean macc = info.getBoolean("macc");
String newFont = info.getString("font");
int newHeight = fontHeight(font);
//Font change, rm is seen as having no font
if (!newFont.equals(fs)) {
if (!fs.equals("rm"))
preamble1.insert(0, '}');
if (!newFont.equals("rm")) {
preamble2.append('\\');
preamble2.append(newFont);
preamble2.append('{');
}
preamble1.insert(0, " fs = " + fs + " nFs = " + newFont + "\n");
fs = newFont;
}
if (height == 0) {
//preamble2.append(" Meow! am = " + accentMode + " fs = " + fs + " mm = " + mathMode + "\n");
}
//Subscripts/Superscripts
if (height > newHeight && newEndX > endX) {//New subscript/superscript
if (newEndY < endY) {//New superscript
//ssstatus.push(SSStatus.SUP);
preamble2.insert(0, "^{");
}
else if (newY > Y) {//New subscript
//ssstatus.push(SSStatus.SUB);
preamble2.insert(0, "_{");
}
//else {
// System.out.println("Please investigate the situation: texcode = " + teXCode + "endY = " + endY + " Y=" + Y + " endX=" + endX + " newEndY=" + newEndY + " newY=" + newY + " newEndX= " + newEndX);
//}
}
else if (height < newHeight && height != 0) {
//ssstatus.pop();
preamble1.append('}');
}
height = newHeight;
endX = newEndX;
endY = newEndY;
Y = newY;
//Enter or leave math mode
if (mathMode && !math && !macc) {
mathMode = false;
preamble1.append('$');
}
else if (!mathMode && !text && !tacc) {
mathMode = true;
preamble2.insert(0,'$');
}
//Accents
if (accentMode) {//If accent mode is ever entered we need to leave it at once
postamble.append('}');
accentMode = false;
}
if ((mathMode && macc) || (!mathMode && tacc)) {//Right now assume that anything that can be an accent is an accent
postamble.append('{');
if (mathMode)
teXCode = maccDict.get(teXCode);
accentMode = true;
}
if (teXCode.charAt(0) == '\\')
return preamble1.toString() + preamble2.toString() + teXCode + ' ' + postamble.toString();
else
return preamble1.toString() + preamble2.toString() + teXCode + postamble.toString();
}
catch(JSONException e) {
return "\\" + shortFontName + "{" + code + "}";
}
}
}
Here is the main class.
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.font.PDFont;
import org.apache.pdfbox.text.PDFTextStripper;
import org.apache.pdfbox.text.TextPosition;
import com.google.common.base.CharMatcher;
import org.json.*;
import java.io.File;
import java.io.IOException;
import java.util.List;
import java.util.Stack;
public class TEX2TXT {
public static void main(String args[]) throws IOException {
TeXUtil util = new TeXUtil();
//Loading an existing document
File file = new File("/Users/CatLover/Documents/Tex/Examples/c4.pdf");
PDDocument document = PDDocument.load(file);
//Instantiate PDFTextStripper class
PDFTextStripper pdfStripper = new PDFTextStripper() {
protected void writeString(String text, List<TextPosition> textPositions) throws IOException {
TeXUtil util = new TeXUtil();
StringBuilder builder = new StringBuilder();
for(TextPosition position: textPositions) {
float Y = position.getY();
float endY = position.getEndY();
float endX = position.getEndX();
PDFont font = position.getFont();
int[] codes = position.getCharacterCodes();
for(int code: codes) {
builder.append(util.fullTextToTeX(font, code, endX, Y, endY));
}
}
writeString(builder.toString());
}
};
//Retrieving text from PDF document
String text = pdfStripper.getText(document);
System.out.println(text);
//Closing the document
document.close();
}
What's really weird is that TeXUtil is constructed every time any white space between words appear while TeXUtil() should be called only once. I'm not sure why this is the case. Since the PDFs are produced by LaTeX and LaTeX does not put white space characters in PDFs but instead leave space between characters to implicitly represent white spaces this may affect how PDFBox works.
You're constructing a new TeXUtil in the first line of your PDFTextStripper subclass's writeString method. If you just remove that line, it should be able to still reference the util defined in your main method (though depending on the version of java you're using, you may have to make it final).

repaint() method not calling paintCompnent

I am trying to make a JFrame program that interfaces a binary-decimal-hexadecimal converter with buttons. A part of this, I would like to draw circles to represent binary numbers in a row of circles with a filled circle representing a one and an empty circle representing a zero. However, when I try to call repaint to draw anything, it does not execute the paintComponent() method, which I know because it does not perform the print statement inside of it. Full code below:
package e2;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.FlowLayout;
public class DecBin extends JPanel {
String theText = "IT WORKS";
int style = Font.BOLD; // bold only
Font font = new Font("Arial", style, 40);
DecBin() {
JFrame f = new JFrame("Decimal to binary and binary to decimal converter");
f.setSize(1000, 1000);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setLayout(new FlowLayout());
Font font = new Font("Arial", style, 40);
JLabel textLabel = new JLabel(theText);
textLabel.setFont(font);
JButton b = new JButton("DectoBin");
b.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a decimal number");
int num = Integer.parseInt(msg);
theText = num + " is " + decToBin(num) + " in binary";
textLabel.setText(theText);
}
});
f.add(b);
JButton d = new JButton("BintoDec");
d.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a binary number");
System.out.print("The decimal form of " + msg + " is " + binToDec(msg));
theText = msg + " is " + binToDec(msg) + " in decimal";
textLabel.setText(theText);
}
});
f.add(d);
JButton hd = new JButton("hexToDec");
hd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a hexadecimal number");
theText = msg + " is " + hexToDec(msg) + " in decimal";
textLabel.setText(theText);
}
});
f.add(hd);
JButton dh = new JButton("DectoHex");
dh.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a decimal number");
int num = Integer.parseInt(msg);
theText = num + " is " + decToHex(num) + " in hexadecimal";
textLabel.setText(theText);
}
});
f.add(dh);
JButton bh = new JButton("BinToHex");
bh.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a binary number");
theText = msg + " is " + decToHex(binToDec(msg)) + " in hexadecimal";
textLabel.setText(theText);
}
});
f.add(bh);
JButton hb = new JButton("HexToBin");
hb.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String msg = JOptionPane.showInputDialog("input a Hexadecimal number");
theText = msg + " is " + decToBin(hexToDec(msg)) + " in hexadecimal";
textLabel.setText(theText);
}
});
f.add(hb);
JButton c = new JButton("Draw");
c.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.print("test1");
validate();
repaint();
}
});
f.add(c);
f.add(textLabel, BorderLayout.SOUTH);
f.setVisible(true);
}
public static void main(String[] args) {
new DecBin();
}
static String decToBin(int d) {
StringBuilder binary = new StringBuilder("");
while (d != 0) {
binary.insert(0, d % 2);
d = d / 2;
}
return binary.toString();
}
static int binToDec(String b) {
int total = 0;
int x;
for (int i = b.length(); i > 0; i--) {
x = Integer.parseInt(Character.toString(b.charAt(i - 1)));
if (x == 1) {
total += Math.pow(2, b.length() - i);
}
}
return total;
}
public void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.red);
g2.fillOval(100, 100, 20, 20);
System.out.print("painted components");
}
static String decToHex(int d) {
StringBuilder Hex = new StringBuilder("");
while (d != 0) {
int remainder = d % 16;
if (remainder < 10) {
Hex.insert(0, d % 16);
} else if (remainder == 10) {
Hex.insert(0, 'A');
} else if (remainder == 11) {
Hex.insert(0, 'B');
} else if (remainder == 12) {
Hex.insert(0, 'C');
} else if (remainder == 13) {
Hex.insert(0, 'D');
} else if (remainder == 14) {
Hex.insert(0, 'E');
} else if (remainder == 15) {
Hex.insert(0, 'F');
}
d = d / 16;
}
return Hex.toString();
}
static int hexToDec(String b) {
int total = 0;
int len = b.length();
for (int i = len - 1; i >= 0; i--) {
if (b.charAt(i) == 'A') {
total += 10 * Math.pow(16, len - i - 1);
} else if (b.charAt(i) == 'B') {
total += 11 * Math.pow(16, len - i - 1);
} else if (b.charAt(i) == 'C') {
total += 12 * Math.pow(16, len - i - 1);
} else if (b.charAt(i) == 'D') {
total += 13 * Math.pow(16, len - i - 1);
} else if (b.charAt(i) == 'E') {
total += 14 * Math.pow(16, len - i - 1);
} else if (b.charAt(i) == 'F') {
total += 15 * Math.pow(16, len - i - 1);
} else {
total += Character.getNumericValue(b.charAt(i)) * Math.pow(16, len - i - 1);
}
}
return total;
}
}
Pertinent code in my opinion is:
DecBin() {
JFrame f=new JFrame("Decimal to binary and binary to decimal converter");
f.setSize(1000,1000);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setLayout(new FlowLayout());
JButton c =new JButton("Draw");
c.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.print("test1");
validate();
repaint();
}
});
f.add(c);
f.setVisible(true);
}
public void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.red);
g2.fillOval(100, 100, 20, 20);
System.out.print("painted components");
}
public static void main(String[] args) {
new DecBin();
}
I have spent hours researching this and have yet to find a solution that will get "painted components" to print.
You do not appear to be adding your DecBin panel to any other UI element. It therefore has no reason to be painted.
You should avoid initializing JFrames inside the constructor of your JPanel child class - it should really be the other way around. That will make things easier to understand (and to debug).

Wordsearch puzzle nullpointerexception on array

Am getting a java.lang.NullPointerException on an array I have initialized and I can't quite figure it out what am doing wrong. The error is occuring at line 371.
Below is the code of the parent class followed by the class initializng the letterArray ArrayList:
package wordsearch;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Line2D;
import java.io.IOException;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingConstants;
/**
* Main class of Puzzle Program
* #author mungaialex
*
*/
public class WordSearchPuzzle extends JFrame {
private static final long serialVersionUID = 1L;
/** No. Of Columns in Wordlist*/
private static final int WORDLISTCOLS = 1;
static JButton[][] grid; //names the grid of buttons
GridLayout myGridLayout = new GridLayout(1,2,3,3);
/**Array to hold wordList*/
ArrayList<String> wordList;
JButton btnCheck, btnClear;
/** Panel to hold Components to the left*/
JPanel leftSidePanel;
/** Panel to hold components to the right*/
JPanel rightSidePanel;
/**Panel to hold word List*/
JPanel wordListPanel;
/**Panel to hold grid buttons*/
JPanel gridPanel;
/**Panel to hold clear button and check button*/
JPanel buttonsPanel;
/**Panel to hold output textarea*/
JPanel bottomPanel;
private JLabel[] wordListComponents;
#SuppressWarnings("rawtypes")
List puzzleLines;
//Grid Size
private final int ROWS = 20;
private final int COLS = 20;
/** Output Area of system*/
private JTextArea txtOutput;
/**Scrollpane for Output area*/
private JScrollPane scptxtOutput;
private Object[] theWords;
public String wordFromChars = new String();
/** the matrix of the letters */
private char[][] letterArray = null;
/**
* Constructor for WordSearchPuzzle
* #param wordListFile File Containing words to Search for
* #param wordSearhPuzzleFile File Containing the puzzle
*/
public WordSearchPuzzle(String wordSearchFile,String wordsListFile) throws IOException {
FileIO io = new FileIO(wordSearchFile,wordsListFile,grid);
wordList = io.loadWordList();
theWords = wordList.toArray();
addComponentsToPane();
buildWordListPanel();
buildBottomPanel();
io.loadPuzleFromFile();
//Override System.out
PrintStream stream = new PrintStream(System.out) {
#Override
public void print(String s) {
txtOutput.append(s + "\n");
txtOutput.setCaretPosition(txtOutput.getText().length());
}
};
System.setOut(stream);
System.out.print("MESSAGES");
}
/**
* Constructor two
*/
public WordSearchPuzzle() {
}
/**
* Gets the whole word of buttons clicked
* #return
* Returns whole Word
*/
public String getSelectedWord() {
return wordFromChars;
}
/**
* Adds word lists to Panel on the left
*/
private void buildWordListPanel() {
leftSidePanel.setBackground(Color.WHITE);
// Build the word list
wordListComponents = new JLabel[wordList.size()];
wordListPanel = new JPanel(new GridLayout(25, 1));
wordListPanel.setBackground(Color.white);
//Loop through list of words
for (int i = 0; i < this.wordList.size(); i++) {
String word = this.wordList.get(i).toUpperCase();
wordListComponents[i] = new JLabel(word);
wordListComponents[i].setForeground(Color.BLUE);
wordListComponents[i].setHorizontalAlignment(SwingConstants.LEFT);
wordListPanel.add(wordListComponents[i]);
}
leftSidePanel.add(wordListPanel,BorderLayout.WEST);
}
/**
* Adds an output area to the bottom of
*/
private void buildBottomPanel() {
bottomPanel = new JPanel();
bottomPanel.setLayout(new BorderLayout());
txtOutput = new JTextArea();
txtOutput.setEditable(false);
txtOutput.setRows(5);
scptxtOutput = new JScrollPane(txtOutput);
bottomPanel.add(txtOutput,BorderLayout.CENTER);
bottomPanel.add(scptxtOutput,BorderLayout.SOUTH);
rightSidePanel.add(bottomPanel,BorderLayout.CENTER);
}
/**
* Initialize Components
*/
public void addComponentsToPane() {
// buttonsPanel = new JPanel(new BorderLayout(3,5)); //Panel to hold Buttons
buttonsPanel = new JPanel(new GridLayout(3,1));
leftSidePanel = new JPanel(new BorderLayout());
rightSidePanel = new JPanel(new BorderLayout());
btnCheck = new JButton("Check Word");
btnCheck.setActionCommand("Check");
btnCheck.addActionListener(new ButtonClickListener());
btnClear = new JButton("Clear Selection");
btnClear.setActionCommand("Clear");
btnClear.addActionListener(new ButtonClickListener());
buttonsPanel.add(btnClear);//,BorderLayout.PAGE_START);
buttonsPanel.add(btnCheck);//,BorderLayout.PAGE_END);
leftSidePanel.add(buttonsPanel,BorderLayout.SOUTH);
this.getContentPane().add(leftSidePanel,BorderLayout.LINE_START);
gridPanel = new JPanel();
gridPanel.setLayout(myGridLayout);
myGridLayout.setRows(20);
myGridLayout.setColumns(20);
grid = new JButton[ROWS][COLS]; //allocate the size of grid
//theBoard = new char[ROWS][COLS];
for(int Row = 0; Row < grid.length; Row++){
for(int Column = 0; Column < grid[Row].length; Column++){
grid[Row][Column] = new JButton();//Row + 1 +", " + (Column + 1));
grid[Row][Column].setActionCommand(Row + "," + Column);
grid[Row][Column].setActionCommand("gridButton");
grid[Row][Column].addActionListener(new ButtonClickListener());
gridPanel.add(grid[Row][Column]);
}
}
rightSidePanel.add(gridPanel,BorderLayout.NORTH);
this.getContentPane().add(rightSidePanel, BorderLayout.CENTER);
}
public static void main(String[] args) {
try {
if (args.length !=2) { //Make sure we have both the puzzle file and word list file
JOptionPane.showMessageDialog(null, "One or All Files are Missing");
} else { //Files Found
WordSearchPuzzle puzzle = new WordSearchPuzzle(args[0],args[1]);
puzzle.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
puzzle.setSize(new Dimension(1215,740));
//Display the window.
puzzle.setLocationRelativeTo(null); // Center frame on screen
puzzle.setResizable(false); //Set the form as not resizable
puzzle.setVisible(true);
}
} catch (Exception e) {
System.out.println(e.getMessage());
e.printStackTrace();
}
}
public int solvePuzzle( ){
int matches = 0;
for( int r = 0; r < ROWS; r++ )
for( int c = 0; c < COLS; c++ )
for( int rd = -1; rd <= 1; rd++ )
for( int cd = -1; cd <= 1; cd++ )
if( rd != 0 || cd != 0 )
matches += solveDirection( r, c, rd, cd );
return matches;
}
private int solveDirection( int baseRow, int baseCol, int rowDelta, int colDelta ){
String charSequence = "";
int numMatches = 0;
int searchResult;
FileIO io = new FileIO();
charSequence += io.theBoard[ baseRow ][ baseCol ];
for( int i = baseRow + rowDelta, j = baseCol + colDelta;
i >= 0 && j >= 0 && i < ROWS && j < COLS;
i += rowDelta, j += colDelta )
{
charSequence += io.theBoard[ i ][ j ];
searchResult = prefixSearch( theWords, charSequence );
if( searchResult == theWords.length )
break;
if( !((String)theWords[ searchResult ]).startsWith( charSequence ) )
break;
if( theWords[ searchResult ].equals( charSequence ) )
{
numMatches++;
System.out.println( "Found " + charSequence + " at " +
baseRow + " " + baseCol + " to " +
i + " " + j );
}
}
return numMatches;
}
private static int prefixSearch( Object [ ] a, String x ) {
int idx = Arrays.binarySearch( a, x );
if( idx < 0 )
return -idx - 1;
else
return idx;
}
class ButtonClickListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
String command = ((JButton)e.getSource()).getActionCommand();
if (command == "Clear") {
//Enable the buttons that have been disabled and not form a whole word
//JOptionPane.showMessageDialog(null, "Cooming Soon");
for (String word : wordList) {
System.out.print(word);
}
} else if (command == "Check") {
String selectedWord = getSelectedWord();
if (!selectedWord.equals("")){
System.out.print("Selected word is " + getSelectedWord());
//First check if selected word exits in wordList
if (ifExists(selectedWord)) {
if(searchWord(selectedWord)){
JOptionPane.showMessageDialog(null, "Success");
wordFromChars = ""; //Reset the selected Word
}
} else {
JOptionPane.showMessageDialog(null, "[" + selectedWord + "] " +
"Does Not Belong to Word list");
wordFromChars = ""; //Reset the selected Word
}
} else {
JOptionPane.showMessageDialog(null, "No Buttons on Grid have been clicked");
}
} else if (command == "gridButton") {
getSelectedCharacter(e);
((JButton)e.getSource()).setEnabled(false);
}
}
/**
* Gets the character of each button and concatenates each character to form a whole word
* #param e The button that received the Click Event
* #return Whole word
*/
private String getSelectedCharacter (ActionEvent e) {
String character;
character = ((JButton) e.getSource()).getText();
wordFromChars = wordFromChars + character;
return wordFromChars;
}
}
/**
* Checks if selected word is among in wordlist
* #param selectedWord
* #return The word to search for
*/
private boolean ifExists(String selectedWord) {
if (wordList.contains(selectedWord)) {
return true;
}
return false;
}
public boolean searchWord(String word) {
if (!wordList.contains(word)) {
return false;
}
//int index = wordList.indexOf(word);
Line2D.Double line = new Line2D.Double();
//System.out.print("LetterArray is " + letterArray.length);
for (int x = 0; x < letterArray.length; x++) {
for (int y = 0; y < letterArray[x].length; y++) {
// save start point
line.x1 = y; // (y + 1) * SCALE_INDEX_TO_XY;
line.y1 = x; // (x + 1) * SCALE_INDEX_TO_XY;
int pos = 0; // current letter position
if (letterArray[x][y] == word.charAt(pos)) {
// first letter correct -> check next
pos++;
if (pos >= word.length()) {
// word is only one letter long
// double abit = SCALE_INDEX_TO_XY / 3;
line.x2 = y; // (y + 1) * SCALE_INDEX_TO_XY + abit;
line.y2 = x; // (x + 1) * SCALE_INDEX_TO_XY + abit;
return true;
}
// prove surrounding letters:
int[] dirX = { 1, 1, 0, -1, -1, -1, 0, 1 };
int[] dirY = { 0, -1, -1, -1, 0, 1, 1, 1 };
for (int d = 0; d < dirX.length; d++) {
int dx = dirX[d];
int dy = dirY[d];
int cx = x + dx;
int cy = y + dy;
pos = 1; // may be greater if already search in another
// direction from this point
if (insideArray(cx, cy)) {
if (letterArray[cx][cy] == word.charAt(pos)) {
// 2 letters correct
// -> we've got the direction
pos++;
cx += dx;
cy += dy;
while (pos < word.length() && insideArray(cx, cy)
&& letterArray[cx][cy] == word.charAt(pos)) {
pos++;
cx += dx;
cy += dy;
}
if (pos == word.length()) {
// correct end if found
cx -= dx;
cy -= dy;
pos--;
}
if (insideArray(cx, cy) && letterArray[cx][cy] == word.charAt(pos)) {
// we've got the end point
line.x2 = cy; // (cy + 1) *
// SCALE_INDEX_TO_XY;
line.y2 = cx; // (cx + 1) *
// SCALE_INDEX_TO_XY;
/*
* System.out.println(letterArray[x][y] +
* " == " + word.charAt(0) + " (" + line.x1
* + "," + line.y1 + ") ->" + " (" + line.x2
* + "," + line.y2 + "); " + " [" + (line.x1
* / SCALE_INDEX_TO_XY) + "," + (line.y1 /
* SCALE_INDEX_TO_XY) + "] ->" + " [" +
* (line.x2 / SCALE_INDEX_TO_XY) + "." +
* (line.y2 / SCALE_INDEX_TO_XY) + "]; ");
*/
//result[index] = line;
// found
return true;
}
// else: try next occurence
}
}
}
}
}
}
return false;
}
private boolean insideArray(int x, int y) {
boolean insideX = (x >= 0 && x < letterArray.length);
boolean insideY = (y >= 0 && y < letterArray[0].length);
return (insideX && insideY);
}
public void init(char[][] letterArray) {
try {
for (int i = 0; i < letterArray.length; i++) {
for (int j = 0; j < letterArray[i].length; j++) {
char ch = letterArray[i][j];
if (ch >= 'a' && ch <= 'z') {
letterArray[i][j] = Character.toUpperCase(ch);
}
}
}
} catch (Exception e){
System.out.println(e.toString());
}
//System.out.println("It is " + letterArray.length);
this.letterArray = letterArray;
}
}
Here is class initializing the letterArray array:
package wordsearch;
import java.awt.Color;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.SwingConstants;
/**
* Reads wordlist file and puzzle file
* #author mungaialex
*
*/
public class FileIO {
String _puzzleFile, _wordListFile;
/**ArrayList to hold words*/
ArrayList<String> wordList;
/** No. Of Columns in Wordlist*/
private static final int WORDLISTCOLS = 1;
List puzzleLines;
JButton[][] _grid;
char theBoard[][];
private final int _rows = 20;
private final int _columns = 20;
WordSearchPuzzle pz = new WordSearchPuzzle();
/**
* Default Constructor
* #param puzzleFile
* #param wordListFile
*/
public FileIO(String puzzleFile, String wordListFile,JButton grid[][]){
_puzzleFile = new String(puzzleFile);
_wordListFile = new String(wordListFile);
_grid = pz.grid;
}
public FileIO() {
}
/**
* Reads word in the wordlist file and adds them to an array
* #param wordListFilename
* File Containing Words to Search For
* #throws IOException
*/
protected ArrayList<String> loadWordList()throws IOException {
int row = 0;
wordList = new ArrayList<String>();
BufferedReader reader = new BufferedReader(new FileReader(_wordListFile));
String line = reader.readLine();
while (line != null) {
StringTokenizer tokenizer = new StringTokenizer(line, " ");
if (tokenizer.countTokens() != WORDLISTCOLS) {
JOptionPane.showMessageDialog(null, "Error: only one word per line allowed in the word list",
"WordSearch Puzzle: Invalid Format", row);//, JOptionPane.OK_CANCEL_OPTION);
//"Error: only one word per line allowed in the word list");
}
String tok = tokenizer.nextToken();
wordList.add(tok.toUpperCase());
line = reader.readLine();
row++;
}
reader.close();
return wordList;
}
/**
* Reads the puzzle file line by by line
* #param wordSearchFilename
* The file containing the puzzle
* #throws IOException
*/
protected void loadPuzleFromFile() throws IOException {
int row = 0;
BufferedReader reader = new BufferedReader(new FileReader(_puzzleFile));
StringBuffer sb = new StringBuffer();
String line = reader.readLine();
puzzleLines = new ArrayList<String>();
while (line != null) {
StringTokenizer tokenizer = new StringTokenizer(line, " ");
int col = 0;
sb.append(line);
sb.append('\n');
while (tokenizer.hasMoreTokens()) {
String tok = tokenizer.nextToken();
WordSearchPuzzle.grid[row][col].setText(tok);
pz.grid[row][col].setForeground(Color.BLACK);
pz.grid[row][col].setHorizontalAlignment(SwingConstants.CENTER);
puzzleLines.add(tok);
col++;
}
line = reader.readLine();
row++;
theBoard = new char[_rows][_columns];
Iterator itr = puzzleLines.iterator();
for( int r = 0; r < _rows; r++ )
{
String theLine = (String) itr.next( );
theBoard[ r ] = theLine.toUpperCase().toCharArray( );
}
}
String[] search = sb.toString().split("\n");
initLetterArray(search);
reader.close();
}
protected void initLetterArray(String[] letterLines) {
char[][] array = new char[letterLines.length][];
System.out.print("Letter Lines are " +letterLines.length );
for (int i = 0; i < letterLines.length; i++) {
letterLines[i] = letterLines[i].replace(" ", "").toUpperCase();
array[i] = letterLines[i].toCharArray();
}
System.out.print("Array inatoshana ivi " + array.length);
pz.init(array);
}
}
Thanks in advance.
Here it is!
char[][] array = new char[letterLines.length][];
You are only initializing one axis.
When you pass this array to init() and set this.letterArray = letterArray;, the letterArray is also not fully initialized.
Try adding a length to both axes:
char[][] array = new char[letterLines.length][LENGTH];
first you will handle the NullPoinetrException , the code is
if( letterArray != null){
for (int x = 0; x < letterArray.length; x++)
{
..........
............
}
}

Exceptions with JAVA loan calculator using JFrame?

I think I almost got it if I can just get rid of a few exceptions the program gives me when I try to run it. Here's the code I have:
package RandomMathGame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class RandomMathGame {
public static void main(String[] args) {
RandomProblemGenerator randomProblems = new RandomProblemGenerator(10);
final int numberProblems = 10;
int correctScore = 0;
JPanel panel = new JPanel();
int answer;
int correctAnswer;
JLabel[] mathProblems = new JLabel[numberProblems];
final JTextField[] mathAnswers = new JTextField[numberProblems];
JLabel[] correctYesNo = new JLabel[numberProblems];
final JLabel score = new JLabel(correctScore + "/10");
JButton submit = new JButton("Submit");
for (int i = 1; i <= numberProblems; i++)
{
final int X = randomProblems.createNumberX();
final int Y = randomProblems.createNumberY();
mathProblems[i] = new JLabel("" + X + " * " + Y + " = ");
mathAnswers[i] = new JTextField();
answer = Integer.parseInt(mathAnswers[i].getText());
correctAnswer = X * Y;
if (answer == correctAnswer)
{
correctYesNo[i] = new JLabel("Correct answer; good job!");
correctScore = correctScore + 1;
}
else
{
correctYesNo[i] = new JLabel("Incorrect answer; try again!");
}
panel.add(mathProblems[i]);
panel.add(mathAnswers[i]);
panel.add(correctYesNo[i]);
}
final int temp = correctScore;
submit.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
score.setText("Score: " + temp + "/10");
}
});
panel.add(submit);
panel.add(score);
JFrame gameFrame = new JFrame();
gameFrame.setTitle("Random Math Game");
gameFrame.setSize(150, 150);
gameFrame.setVisible(true);
gameFrame.setContentPane(panel);
}
}
And these are the exceptions it's giving me when I run it:
Exception in thread "main" java.lang.NumberFormatException: For input string: ""
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:504)
at java.lang.Integer.parseInt(Integer.java:527)
at RandomMathGame.RandomMathGame.main(RandomMathGame.java:33)
Java Result: 1
I'm crunched for time, so any help would be much appreciated.
You are trying to get from a field you just created which is blank.
mathAnswers[i] = new JTextField();
answer = Integer.parseInt(mathAnswers[i].getText());
So in this you are just checking from wrong place.
Seems like on first step you want to create the text fields and the second line should be there at some other event.
Hope it helps
String answerStr = mathAnswers[i].getText();
if(answerStr.isEmpty()){
correctYesNo[i] = new JLabel("Not a valid answer/answer field empty!");
} else {
answer = Integer.parseInt(answerStr);
correctAnswer = X * Y;
//Rest of your code goes here
}
Hope this helps you!
answer = Integer.parseInt(mathAnswers[i].getText());
Is what's causing the error. This is because one of your textfields is blank. Do some validation before accepting user input, unless you want your application to go awry.

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