How To Trace WiFi Near Some Source In JAVA
Sep 9, 2014I want to trace how many wifi signals are available near some source within some distance in JAVA. How do I do that?
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Java Classes - Trace Methods Calls
Apr 1, 2015Consider the two simple Java classes below:
Java Code:
class Computer {
Computer() {
System.out.println("Constructor of Computer class.");
}
void On() {
System.out.println("PC turning on...");
}
void working() {
[Code] ....
After the program run, how do I trace (1) which object call which method (2) and how many times?
How To Trace Method Calls
Apr 1, 2015Consider the two simple Java classes below:
class Computer {
Computer() {
System.out.println("Constructor of Computer class.");
}
void On() {
System.out.println("PC turning on...");
[Code]...
After the program run, how do I trace (1) which object call which method (2) and how many times?
Trace Table - Use Of Iterators?
Feb 20, 2014I'm confused on how to provide a trace table with this problem.
int i = 0; int j = 1; int n = 2;
while (i < 10) {i++; n = n + i + j; j++; }
My professor wants us to use iterations as a way to solve it and this was the example given:
int i = 0; int j = 1; int n = 2;
while (i < j) { i ++; j --; n++; }
public static String r43a() {
// START CODE
String answer = "iteration1: i=" + 0 + ", j=" + 1 + ", n=" + 2 ;
answer += "
";
answer += "iteration2: i=" + 1 + ", j=" + 0 + ", n=" + 3 ;
return answer;
// STOP CODE
}
How To Trace Methods Calls
Mar 31, 2015Consider the two simple Java classes below:
class Computer {
Computer() {
System.out.println("Constructor of Computer class.");
}
[Code]...
After the program run, how do I trace (1) which object call which method (2) and how many times?
No Java Source Files In Projects?
Apr 10, 2014my course material is due for term 1 of my cert 4 programming course, but My lecture will not pass my java projects because there is no source files generated for them in the net beans project structure, tried building, cleaning and building, all i can think of?, tried IDE's 7.4 and 8.0 .
View Replies View RelatedCompile Java Source Files At Runtime In JRE
Feb 14, 2014I am looking for a way to compile Java Source-Files at runtime and save them all in an executable jar; almost like an IDE would do. I know that there is the javax.tools package which provides a JavaCompiler interface and you can use ToolProvider.getSystemJavaCompiler() to get an instance of a compiler. However, this method has one important problem: it only works on machines that have the JDK installed. Not when only the JRE is installed.
I guess at this point that I need some kind of third party library that offers an implementation of a JavaCompiler. Unfortunately, this is really complicated to search for on the internet since all top listings when searching "compile java at runtime jre" do not really provide a solution to the problem.
I am writing a (somewhat) complex simulation software right now which is supposed to be used by people who have absolutely no knowledge of programming. At the same time, this software should provide the user with a certain amount of flexibility and control over the flow of the simulation.
My previous take on this problem was to build a complex system to interprete user settings from a GUI. I would basically read the GUI input, output it to some kind of own scripting syntax which I just quickly made up and have that interpreted at runtime. Then I realized, that is a silly concept and I threw it out before I got far into the developement.
The much better solution I came up with is taking the input from the GUI, create java source code from it and compile it at run-time. Seems much cleaner and nicer to me; will also probably have a better performance, but thats not really an issue anyways.
How To Organize Queries In Java Source Code
Oct 7, 2014Lately I've been working with JDBC and writing queries in some Java programs. I've noticed that I keep experimenting with where I place my blocks of querying code. I've tried creating a private method in the class where the query is used, I've created utility classes where I can call the query when needed, and sometimes I've just put it in a localized block of code where I need to. Also, most often these queries are one-shot queries where I need to pull the data to populate a JTable.
In short, this has made me realize that I don't have a solid practice for organizing my queries in Java. So my question is "Is there a practice for organizing query code?".
Many Errors For A Missing File In Stack Trace
Mar 6, 2014Why do I see many exceptions for one missing file on the stack trace ? My guess is, where ever that file or methof is being called , all of them will throw exceptions. So, where do I find the root exception, first one which is thrown OR the last one ?
java.io.FileNotFoundException: c: emppw.txt (The system cannot find the file specified)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:120)
at java.util.Scanner.<init>(Scanner.java:636)
at com.rbc.ReportDriverRunner.getPassword(AuditReportDriverRunner.java:39)
[Code] ....
In the above stack trace, "java.io.FileNotFoundException: c: emppw.txt (The system cannot find the file specified)" is the root cause (Assuming there is only one error which causes code to fail) ? Is the first one cause of failure whch then cascades failure of other methods ?
How Java Finds Jar Contents Imported In A Source File
Feb 10, 2015how java imports libraries from a jar file inside a source. Let's say I have the following code on Something.java file,
import com.mycomanyA.*;
import com.mycomanyB.*;
public class Something{
public static void main(String ... args){
// code goes here...
}
}
And the Something.java is inside the following structure...
A.jar
com/
mycompanyA/
A.class
Another.class
B.jar
com/
mycompanyB/
B.class
neededImage.gif
bin-folder/
org/
apache/
Something.java
To compile this code(Something.java) from command line I want to use the following command,
javac org/apache/Something.class
And for the compilation to be successful, I'll have to be just above bin-folder because...
- > Only then my default class path will be (.) and java would automatically include A.jar and B.jar(the other way is to add the jar files using -cp argument, which I want to avoid in this scenario)
- > And for the import org.mycompanyX to work I'll have to be in the (.) directory.
Are my assumptions correct about how java find jar contents imported in a source file?
Open Source Java API For Creating Tasks To MS Outlook?
May 28, 2014I am looking for pure java API to be able to create/read outlook tasks.
Any open source API's available for the same.
Scanning And Displaying Every Word From A Website Source Code Java
Feb 19, 2014I have been given a task to scan the contents of a websites source code, and use delimiters to extract all hyperlinks from the site and display them. We havent been told anything about how to do this so after some looking around online this is what I have so far:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Scanner;
[Code] ....
So my program can extract each line from the source code of a website and display it, but realistically I want it to extract each WORD as such from the source code rather than every line. I've looked around online but I don't really know how it's done because I keep getting errors when I use input.read();
How to make it extract each word from the source code?
Java Source Code File Naming With Access Modifiers
Feb 3, 2014Why is this not valid in java:
Both uses public with the same class/interface name.
Test.java:
public class Test implements Test{
/// Some codes
}
public interface Test {
///Some methods
}
How To Deploy Java Swing Application For Windows Without Revealing Source Code
Feb 21, 2015How to deploy Java Swing application as windows software. I have tried the following to do this :
I have created jar file for my project after that created exe file using Launch4j and Advanced installer, exe file produced by both software are working fine but those are placing the jar file inside that exe file, My problem is any one who has that exe file can extract and view the source code by decompiling java class file. Is there any way to deploy java application without decompiling the code.
Read In Java Source Code File As Command Line Argument
Oct 31, 2014I am trying to complete this question. I understand the most of it but I haven't go a clue to read in the file name.
Full question: Implement a program that reads in a Java source code file and checks to see if it has balanced {}brackets. Your program should use a stack, implemented as a linked list, to check the brackets.
NOTE: you can use a reference called top which points to the head of the list. Your program should run as a command line program and should take a filename as an argument and print one of BALANCED or NOT BALANCED.
For example: c:> java checkBalanced "myProgram.java" BALANCED
Add Source To Bat File?
Aug 30, 2014Have the following .bat file that compiles the ReadMindWave.java source with jna and jfreechart. I get a javac error saying 'no source' when the .bat is run, as the .java source needs to be included in the .bat file. Where it goes in the following .bat file?
@echo off
echo Compiling %1 with JNA and JFreeChart...
javac -Xlint:deprecation -cp "C:jna-master*;C:jfreechart-1.0.19libjfreechart-1.0.19.jar;C:jfreechart-1.0.19libjcommon-1.0.23.jar;."%*
The file to compile is in C:MindWaveTestsReadMindWave.java
Mvn Repository Go-to Source For Jar Downloads?
Jun 20, 2014I notice when I look to download library jars, I keep ending up at Maven Repository: Search/Browse/Explore. I wonder is this really the de-facto place to download jars for java libraries? Right now I want to use the apache commons net library in order to build an imap server. And I find myself again mvnrepository:Is this where I should be downloading jar files?
View Replies View RelatedSource File Input
Jun 8, 2014how to add an error message when my program can't find the file the user inputs.
For example:
Enter your source code:
D:Data StructsProjectssrcHelloWorld (I didn't put .java on purpose)
Exception in thread "main" java.io.FileNotFoundException: D:Data StructsProjectsAssignment 3srcHelloWorld (The system cannot find the path specified)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileReader.<init>(Unknown Source)
at HomeworkDriverFour.main(HomeworkDriverFour.java:14)
//Can I get rid of the exception above and replace it with "File not found!"
Enter your source code:This is what I have so far:
import java.io.*;
import java.util.*;
public class HomeworkDriverFour {
public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
[code]...
ImageIO Unknown Source?
Apr 9, 2015I am having errors but not sure why.
My two classes. I have pointed out the lines that are causing the errors. -
import gfx.SpriteSheet;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
[Code] .....
Source File Compilation
Jan 22, 2015when i try to compile following source file, there is a error which states "MovieTestDrive is public, so must be declared in a file MovieTestDrive.java" i didnot understand. i am beginner in java;
class Movie
{
String title;
String genre;
int rating;
void playit()
{
System.out.println("playing the movie");
}
}
public class MovieTestDrive
[code]....
Javac Not Finding Source Files
Apr 3, 2015In using javac, I have installed the JDK, set the PATH and JAVA_HOME. When I run this:
"C:Program FilesJavajdk1.8.0_40injavac" -cp C:Gj_javacHTMLCarbonResults.java
I get: javac: no source files
Since I placed the source file path in the command line, I don't understand why it can't find the one .java file.
Swing/AWT/SWT :: Where Is Event Source Object
Feb 28, 2015java.awt.Component is an abstract class, and it's direct Sub-classes are Button, Canvas, Checkbox, Choice, Container, Label, List, Scrollbar, Text Component
So, when I use addXListener(mylistenerclass m);//which is a method of Component class which object is holding the list of all listeners, for a particular Event Source?
I am under the assumption that - there is an Event Source Object(possibly static) for every Event Source type(mouse, keyboard etc) that holds a list of destinations(classes that implements their listener interface) - added to the the object via addXListener method. When an event happens(mouse click, drag etc) the Event Source Object creates an Event Object and send it to all the destinations. Is my assumption correct? I can't seem to find the location or declaration of Event Source Object and the list where it stores it's registered destinations.
Source Code For Pre-defined Methods?
Jul 11, 20141.Is there any way by which i can see what is happening inside pre defined methods.
i.e. can i see there source code?
2.Somewhere i learned how to see the content of a pre defined class i.e. by using:
javap java.io.classname
but i dont know what javap means!
Using Enumeration Of One Source-code File In Another?
Mar 30, 2014To be specific, how can I use enumeration of one source-code file in another.
View Replies View RelatedDefining A Class In Source Code File?
Oct 9, 2014 "If you define a public class or an interface in your class, then it should match the name of the java source code file."
Does the statement above mean the following should compile fine ?
public class Animal{
public class Animal{ }
}
The author gives an example saying that if you have a class Multiple.java and in that class, you have:
public class Multiple{}, then it should compile.
But this does not compile. I tried it.
How To Read Input Of Source Code With FileReader
Oct 19, 2014I'm doing homework and as far as input, my assignment reads: "Your program must take as input the name of a Java source code file such as the source file containing the source code of this assignment." So my question is, how do i do that without linking the directory directly (i.e. C:/users/...)? I'm using FileReader as shown below...
public static void main(String[] args) throws Exception {
FileReader file = new FileReader (WHAT GOES HERE???);
BufferedReader reader = new BufferedReader(file);
String s = "";
String line = reader.readLine();
[Code] .....