I want to read and write json to/from a file. I read the following document:
JsonReader (Java(TM) EE 7 Specification APIs)
I try to define a JsonReader object in Eclipse:
JsonReader jr
But there appears to be no import for it. Where I am supposed to get the Json library?
I'm rather new to programming and I'm trying to make a gui program that will allow the user to create text files. They will be prompted to enter what they'd like to save their file as and then they will be allowed to input text to that file . They will also be allowed to open their files to modify or view its contents. So to start things off, I'm making a prototype if you will.. I've been able to save to a file the problem occurs when I try to read/display it.
Main Class:
public class MainActivity {
public static void main(String[] args) {
// Access to other classes
WriteFile writer = new WriteFile();
ReadFile reader = new ReadFile();
[Code] ....
My background is mainframe and i'm new to java. We're moving from mainframe to the java world and I'm trying to achieve a task. I have a main folder and then bunch of sub folders and each sub folder has bunch of xml files, files size are varies some of them are 900kb. I need to read these xml files and send the output to the txt file (comma separated).
Some possible options or sample example... Please find below the sample xml file. I need to extract information's only where
FORM name="F00001".
[CODE]<PACKET>
<FORM name="F00001" sequence="0">
<FIELD sequence="1">02</FIELD>
<FIELD sequence="2">00000</FIELD>
<FIELD sequence="3">CAB100</FIELD>
<FIELD sequence="4">TEFAP001</FIELD>
<FIELD sequence="5">EMPTY FIELD</FIELD>
<FIELD sequence="6">009.999.989</FIELD>
[Code] .....
I wanna learn to create a method where I use a scanner or any other way to input.The stuffs I input will be strings. The whole thing will be like a destination creator.So if I input the string USA, it will write this to a file:
1:USA
When I go to the method again the ID will be added so if I input UK, the file will contain:
1:USA
2:UK
Now if I terminate the program, next time when I run it again it will be able to read the ArrayList, so if I wanna go to the method again and write: Norway the file will contain:
1:USA
2:UK
3:Norway
Later I also want to be able to use println to show all of these lines from the file, as well I would like to be able to delete an ID, so if I delete ID 2 the file would contain:
1:USA
3:Norway
I'm quite new to Java, I'm in a Java course since soon 3 weeks back and I have sure learned a lot, all the loops and basic statements that exist in most languages, but now when it comes to this I just don't understand.
I got a question in my last interview, its all about multithreading, interviewer asked me to write a program, to write the contents of three files(F1,F2,F3) in to a new File F4, using multithreading , first thread should read the first file and second thread should read second file, so the File F4 should contain F1's contents in first then F2's contents after that etc. I tried to give my best shot, but i couldn't get a way to ensure that the first thread is reading the first file and write to F4 then second thread reading the second file and writing once first file is written completely into F4 and so on ..how to do this?
View Replies View RelatedWhat i basically do is that i read the information of what course that needs to be updated with a new course date and then i log into the wordpress page and navigate to the course and add the date.
I need the java program to be able to do these following actions.
1. Open a webpage
2. write to a form
3. click a button
4. search for a text on screen
5. click on a specific place on the screen/click on a link
6. read from an excel file.
and so on...
I have a JSON string
Java Code: {
"AvailableDeliveries": {
"500": {
[Code]....
Number of JSON object can vary. I tried to generate POJO from jsonschema2pojo but it generate fix number of object inside AvailableDeliveries class. How I can define a POJO with collection of object and map corresponding field for above JSON string. I can't change the structure of JSON response as I am consuming the string.
I would like some clarification on a project I am working on. I need to build a java application to query a xml and json file. I have started by parsing both documents and I am unsure if I am doing the next steps correct. I was thinking about dropping the txt file with both outcomes into a db and doing it that way, is this the right way or is there a better and more efficient way of doing things ?
View Replies View RelatedI have written my program result into a json file but i am getting json file in below format.
{"one":"one","two":"two","three":"three"}
but I have lot of entries to write into json finally it become unreadle format which is not very compart to read.
Is there any way to format or writing line by line into json file like below format,
{
"one":"one",
"two":"two",
"three":"three"
}
reading a large json file which is really huge and it contains pair of id and URL in a array as shown below.. i need to get this all id and URL from this file in my java code and need to perform operations . how to read such a big file and store the contents in java code to process it further.
{
"Array": [
{
"id": "1test",
"URL": "http://servername/test/1test.html"
},
{
"id": "2test",
"URL": "http://servername/test/2test.html"
}
....................many id and URL in the same Array which makes the file Huge..
]
}
I am trying to do a read/write int property called currentQuestionIndex. This property is the index of the question currently selected, and the value of the property is 0 when a DrivingTest object is first created. I dont understand how to do this. I am not sure how to get the index of the current question. i was trying to use an iterator but i dont think i was doin it right. My question class that hold all my data
package cs320Labs.servlet;
public class Question {
String description;
String answerA;
String answerB;
String answerC;
int correctAnswer;
[Code] ....
How can i use java for usb device? I want to read or write in a usb device in java. I've looked for in the web and i didn't find anything!
View Replies View RelatedI have seen different methods of creating and reading files (specifically text files) in Java. The PrintWriter method or the Formatter with a Scanner to read the file, using a BufferedWriter with a BufferedReader, etc. They will all read/write text files, but from what I understand they do so in different ways. When would it be more beneficial to use a buffered writer than, say, PrintWriter, which is much simpler code-wise? Is there a "best" way to handle i/o in general in Java?
View Replies View RelatedI have a question for the read and write method in file.In my code for writing i m using PrintWriter and for reading Scanner.So i m saving data to file and when is need it i m reading from the file.but i also have to delete specific data from it.Is there a way to delete a specific line from the file?When i google my problem i found that is better to save your data to temporary file and then to the final.
View Replies View RelatedTo read or write to a USB device must use an external library?
Such as this? usb4java - About
I have a database of 100,000 research articles, all as full text. From a GUI I'm building ( w. Scene Builder and NetBeans) I would like to enter a journal name and have some of the articles read into memory, in a background thread. Then I would analyze them, also in a background thread. Then I would write various results, e.g., lists of authors or titles, wordlists, to the GUI for examination by a user.
How to create background threads from my model that will read from and write to a GUI using Tasks and/or Services.
Write a program that reads an integer and displays, using asterisks, a filled diamond of the given side length. For example, if the side length is 4 the program should display.
*
***
*****
*******
*****
***
*
I have it where it displays the top half of the diamond. But i cannot figure out how to get it to draw the bottom half.
import java.util.*;
public class E616 {
public static void main(String[] args) {
Scanner input=new Scanner(System.in);
System.out.print("Enter number of rows. ");
int N=input.nextInt();
[code]...
Write a java program to read the time intervals (HH:MM) and to compare system time if the system time between your time intervals print correct time and exit else try again to repeat the same thing. By using StringToknizer class.
View Replies View RelatedI designed a Java desktop application (i.e the app runs on local computer), everything is fine until when I compiled the program and wanted to run it on another computer then it tell me "java.sql.SQLException: attempt to write to only read database".
View Replies View RelatedI have a requirement to read all the xml files from a parent folder and write in a spreadsheet(separate spreadsheet for each xml file)
I have written the below code in which xml and excel file name are hardcoded. The format of xml file is same.
package xmlexcel;
import org.apache.poi.hssf.usermodel.*;
import java.util.ArrayList;
import java.awt.List;
import java.io.*;
import java.util.ArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.SAXException;
[Code]...
Ex. If I type 5943, the program will say
mill = 5
hun = 9
ten = 4
uni = 3
get the picture I had to translate the decimal value names from a different language.
This is what I have tried...,
Java Code:
import java.util.Scanner;//Permite el uso de leer el teclado del usuario
public class DeterminarValorDecimal//Nombra el documento
{
public static void main(String [] args)//Podemos ver la clase
{
[Code].....
But what this does is I have to enter the single digits one by one. I want to be able to type the whole number. Is there a method that reads the length of the whole number and lets me classify each digit so I can do what I want to do?
We're learning how to use Binary I/O commands...which equates to....
My issue is trying to relate the Fraction objects (which we are to create using a loop) with the read/write methods used in Binary I/O (input/output streams). I left a blank after the output.write(), so you can see where the issue exist.
Java Code:
import java.io.*;
public class FractionTest {
public static void main(String[] args) {
int [] fraction = new int[3];
for(int i = 0; i <= fraction.length; i++){
Fraction numbers = new Fraction();
[Code] ....
I have a question regarding the permissions set for generated heap dumps.
I have some Jetty servers running on Linux (Java 6 64 bit / Java 7 64 bit) with the following Java arguments:
-XX:+HeapDumpOnOutOfMemoryError
-XX:HeapDumpPath=/opt/apps/heapdump
When there is a out-of-memory exception a heap dump is automatically generated by the JVM. But it seems that the heap dump permisions are set to read-write for owner only (600).
When I create files then they have by default read-write for owner and group/all read access (644).
$ ls -l
total 795432
-rw------- 1 bamboop bamboo 811322265 Apr 14 09:18 java_pid337.hprof
-rw-r--r-- 1 bamboop bamboo 6 Apr 14 12:57 test
Here the umask set for the server running the Java processes
$ umask
0022
1. creates a file.
2. ask user to write into that file
3. save the file
4. print content of file.
Is my current exercise, so far i have gotten the code to create a file. What should i use to ask user to write into that file and save?
package assignment7;
import java.io.*;
public class Exercise2
{
public static void main ( String [ ] args ) {
String filePath="newfile.txt";
File newFile = new File ( filePath ) ;
[Code] .....
1. creates a file.
2. ask user to write into that file
3. save the file
4. print content of file.
is my current exercise.so far i have gotten the code to create a file, and ask the user to input their age.what should i use to save what the user writes into the file?
Java Code:
package assignment7;
import java.io.*;
import java.util.*;
public class Exercise2
{
public static void main ( String [ ] args ) throws IOException
{
Scanner scan = new Scanner(System.in);
[code]....
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data.
Here is the base Product class that must be used to create the objects for the array.
public class Product
{
public String pName;
public String stringName;
public double price;
public int quanity;
[Code] .....
And then here is the data from the text file that i must extract to use to create product objects.
Dill Seed,938,34
Mustard Seed,100,64
Coriander Powder,924,18
Turmeric,836,80
Cinnamon (Ground Korintje),951,10
Cinnamon (Ground) Xtra Hi Oil (2x),614,31
Cinnamon (Ground) High Oil (1X),682,19
These continue for about 40-50 entries, they are not separated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name separated with spaces, then price after a comma, then quantity after the second comma.....