Going Through All The Keys On Keyboard One At A Time

Jul 14, 2014

I am writing a code that tries to figure out the users password by going through every possible key (brute force). Although I think its going to work, it looks EXTREMELY inefficient to me, since its just a huge switch statement for each character -- 94 total, including the shift values. Is there a built in method in the JAVA API that goes through every key or something?

Here is my code for that segment:

public char[] HackingPassword(){
char[] passChars = this.password.toCharArray();//convert the password to char[]
char[] hacking = new char[passChars.length];//make the hacking variable same size as users password
int nextCharValue = 0;//this is used to cycle through the keyboard
//check each letter of hacking to match with password
for(int i = 0; i < passChars.length; i++){

[Code] .....

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Java 2D Game - Overcoming Max Of Three Keys At A Time Limitation Of Keyboard

Jan 7, 2014

I'm working on a Java 2D game which requires a max of six keys be held down at the same time.

The game is for two players on the same keyboard, playing simultaneously.

However, all three computers I ran the program on only allow a max of three keys held at a time. They all have trouble with reacting to more than three keys being held.

It seems that pressing a new key after three are already held, either cancels some other key-holding or is ignored.

I've been told that this is a hardware issue. Most keyboards can't handle more than three keys held at a time. But a lot of games do require this, and they do not require special gaming-keyboards to run on my computer without problems.

So there has to be a solution that will make the game playable on any standard keyboard.

(I use Key Bindings).

The game's controls:

Player 1

- Rotate sprite and set angle of movement: LEFT arrow

- Rotate sprite and set angle of movement: RIGHT arrow

- Move forward: UP arrow

- Shoot missile: ENTER key

Player 2

- Rotate sprite and set angle of movement: 'A' key

- Rotate sprite and set angle of movement: 'D' key

- Move forward: 'W' key

- Shoot missile: 'T' key

Relevant code:

The Key Bindings part:

Java Code:

// An action for every key-press.
// Each action sets a flag indicating the key is pressed.
leftAction = new AbstractAction(){
public void actionPerformed(ActionEvent e){
keysPressed1[0] = true;

[Code] .....

This is mostly how reacting to key-presses and key-releases works in my program. When a key is pressed or released, a flag is set. The Board class reades the flags every game-loop cycle and reacts accordingly.

As I said, the program doesn't react correctly to more than 3 keys held at a time, probably because of the keyboard. Is there a way to code a solution?

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Apr 5, 2014

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Microsoft/ORGANIZATION ,/O Nelly/PERSON !/O '/O

Now we notice that microsoft is and organitzation and "," is Other and Nelly is a person's name and so on ..

Now I am asked to return the numbers of tags in the text which is 4 in our case because we have (ORGANIZATION,PERSON,LOCATION,OTHER)

My question here is my logic true ? And since i made a map of String,String ; Is there any way that i can get the size of the values in our case the values are the organization etc.. ?

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;

[code].....

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Feb 9, 2014

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Oct 22, 2010

I am new with java, eclipse, jpa(eclipselink), postgresql, and trying to make a web application. I have two tables:

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trades: bidid, askid, quantity, price

bidid and askid columns are foreign keys from bids table (id), and they are the primary key for the trades table.

I created the Entities from the Tables (Bid and Trade class) with eclipse and it generated a TradePK class for the primary key.

Trade.java:

@Entity
@Table(name="trades")
public class Trade implements Serializable {
@EmbeddedId
private TradePK id;

[Code] ....

I understand that this is necessary because the primary key is from two column, but as soon I want to persist a Trade back to the database Eclipselink call the column names twice:

INSERT INTO trades (price, quantity, datetime, BIDID, ASKID, bidid, askid) VALUES (?, ?, ?, ?, ?, ?, ?)

So postgres give me back an exception: ERROR: column "bidid" specified more than once

And I don't know why. According to the JPA docs I didn't found any mistake:

Introduction to EclipseLink JPA (ELUG) - Eclipsepedia

Or I just can't see it... or is there a better doc which explains it better?

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Jul 4, 2014

I want to write a method to print the all the names of a phone book. phoneBook is a HashMap<String, String> , that has names as keys and phone numbers as values.

Reading the documentation for both HashMap and Set, I have more or less an idea of how it could be done but I cant put it on code..
 
public String getName()
{
  String[] keys = phoneBook.keySet().toArray();
return keys[0];
  }

This is wrong. It doesnt compile saying incompatible types. I was thinking first to manage to succeed to get a key from my phone book and then I change it to print all the keys.

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Aug 12, 2014

I am trying to work with a SQL database and some JSF pages that were created with/for CRUD. The data comes up just fine but all my foreign keys show the primary key for the key not the data. So instead of having the actual Zone I get the number (my primary key) that matches the Zone.

example:
4717A Cool ReceptionTitle: Gatherer of Cool Companycom.vancowboy.lotor_db.LotroZones[ id=11 ]

The last item should read "All" not "com.vancowboy.lotor_db.LotroZones[ id=11 ]"

This was straight from a tutorial so I can learn this but the FK has got me baffled...

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I have the following hashMap declared:

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Apr 22, 2014

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Feb 9, 2015

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I need the output time to be the time the class started, plus the length of the class, and displayed in military time.

for example,

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I can't for the life of me figure out how to do this. I have gotten a program that works for this time and minutes, and displays the correct 1020. But when I change the information to say

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I get:

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90 is technically correct, the way the formula is setup, but I need it to display 0900 not 90.

Here is the code that I have. Be easy, I'm still learning, and this is just the file I created to get the formula to work. Also, the verbose in here is just for my own debugging to make sure values should be what I'm expecting them to be.

public class calc
{
public static void main(String[] args) {
double hours, minutes, length;
double temp;
int time = 2400;
hours = time / 100;
System.out.println("Hours are: " + hours);

[Code] ....

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Dec 13, 2014

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int i;
i =0;
for (String name: exampleOne.keySet())

[Code]....

Now I want to return all values that associated with one key. How do I do this? Or is it possible to other way round? I mean return All keys associated with a value?

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Aug 27, 2014

I am developing a java code using netbeans for encryption decryption by RSA algorithm. Swings and file handling play a major role in these code. My encryption code is working nicely but the code for decryption is not since keys file is not being read. That is why variable mod and pri are getting null values and the following error stack is coming. I know where the problem is somewhere in void readkeys() function but cannot solve it.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.math.BigInteger.modPow(BigInteger.java:1579)
at rsakeydecryption1.RsaKeyDecryption.decryption(RsaKeyDecryption1.java:167)
at rsakeydecryption1.RsaKeyDecryption.read_output(RsaKeyDecryption1.java:294)
at rsakeydecryption1.RsaKeyDecryption.actionPerformed(RsaKeyDecryption1.java:330)

[Code] .....

My code for decryption is

package rsakeydecryption1;
import java.math.BigInteger;
import java.util.Random;
import java.io.*;
import javax.swing.*;

[Code] ....

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Mar 15, 2014

Suppose that a certain BST has keys that are integers between 1 and 10, and we search for 5. Which sequence below cannot be the sequence of keys examined?

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(b) 4,10, 8, 6, 5
(c)1,10,2,9,3,8,4,7,6,5
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I've noticed many differences, such as there is only one with an odd number of keys, and one has all integers from 1-10 inside of it, but I can't find any real reason that you wouldn't be able to search it?

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Aug 3, 2014

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Play Mini Sports Challenge game online - Y8.COM

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Nov 21, 2014

I need to get a clone of a fairly deep object tree. All objects are entities and I need to set the primary keys to null. The root object:

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@OneToMany(cascade = CascadeType.ALL)
@JoinColumns({
@JoinColumn(name = "gesamtentscheidung_dstNr"),
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[Code] .....

When I call

Grundentscheidung grundentscheidungClone = grundentscheidung.clone();

grundentscheidungClone contains the whole object tree with all dependencies, but the Tatbestand objects have their primary keys. When I use the debugger I see that Tatbestand.clone() is never called.

Is my code faulty? I would like to avoid to write a large method which sets all primary keys on the object tree to null.

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import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.LinkedList;
import java.util.Random;

[code]....

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Feb 16, 2015

My objective here is to process a HashMap's key's in order. I found SortedSet as a way to do it.

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[Code] ....

This is the method I am trying to write

public void displayAllYearsAndWinners_2()
{
// Creation of the SortedSet
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[Code] ....

However, the compiler gives me a warning of NobelPrizeWinners.java uses unchecked or unsafe operations. Recompile with -Xlint:unchecked for details.

As I said, my objective here is to process them in order. If this compiler warning cannot be resolved, I am open to other methods of accomplishing my objective.

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Jan 29, 2014

I have two classes. time_runner is used for testing my code.

This is what I'm using to test my code:
 
class time_runner
{
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System.out.println("time1: " + time1);
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[code]....

The two constructors are "Time()", which is the default constructor that sets the time to 1200, and "Time(int h, int m)" Which says If h is between 1 and 23 inclusive, set the hour to h. Otherwise, set the hour to 0. If m is between 0 and 59 inclusive, set the minutes to m. Otherwise, set the minutes to 0. Those are my two constructors that I pretty much have down. The three methods however I'm having trouble with. The "String toString()" Returns the time as a String of length 4. The "String convert()" Returns the time as a String converted from military time to standard time. The "void increment()" Advances the time by one minute.

public class Time {
private int hour;
private int minute;
  public Time(int h, int m) {
if(h > 1 && h < 23)
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[code]....

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Sep 4, 2014

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[Code].....

Note: If I uncomment line num 9 it works fine

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Feb 20, 2014

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The program should read the name of the file from the keyboard.

************************************************** ************************************************** **************

I need to get the filename from the user for this particular program. Usually I would have the name of the file prewritten into the source code like this....

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I tried different ways but I just can't seem to figure it out.... I guess what I'm really asking is how to rearrange Scanner input = new Scanner(new File("gettsy_burg.txt"); since I want the user to input the filename instead of the filename being prewritten by the programmer(me).

This is what I have so far to let the user for input....

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************************************************** ************************************************** **************

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[code]....

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Jun 21, 2014

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[Code] .....

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