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Java program not working using the command line

Short story :
When I run my java application through the Intellij it's all working.
When I run it through the command line I have some issues.
Long story:
First, I have to say that I have a 'lib' folder inside my project with all the Jars I need and I added it as a Library to the project.
When I compile it from the command line I have to specify a '-cp' to the lib folder, otherwise it doesn't load the jars. Even though it looks good, when I run my java application, I get a 'Error: Could not find or load main class awsUpdater' error
My commands :
For compiling -
javac -cp "../../../../lib/*" awsUpdater.java
For executing -
java -cp "../../../../lib/*" awsUpdater
Here's my class (besides the methods)
package AWSUpdater;
import com.amazonaws.AmazonClientException;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.auth.DefaultAWSCredentialsProviderChain;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3Client;
import com.amazonaws.services.s3.model.GetObjectRequest;
import com.amazonaws.services.s3.model.PutObjectRequest;
import com.amazonaws.services.s3.model.S3Object;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class awsUpdater {
public static void main(String[] args) throws IOException {
String bucketName = "bucket";
String key = "ket";
//AmazonS3 s3Client = new AmazonS3Client(new ProfileCredentialsProvider());
AmazonS3 s3Client = new AmazonS3Client(DefaultAWSCredentialsProviderChain.getInstance());
System.out.println("Downloading an object");
S3Object s3object = s3Client.getObject(new GetObjectRequest(
bucketName, key));
//Get new version of android
String newAndroidVersion = getNewAndroidVersion();
//Download current versions.json
String currentJson = displayTextInputStream(s3object.getObjectContent());
//Edit versions.json with new android version
String editedJson = editJsonWithCurrentAndroidVersion(currentJson, newAndroidVersion);
//String editedJson = editJsonDummyCheck(currentJson);
//Create new file to upload to S3
createFileWithNewJson(editedJson);
//Upload new file to S3
updateVersion(bucketName, key, "versions.json");
}
Would appreciate any help with how to compile and execute my program through the command line. thanks !

you need to add package name
java -cp "../../../../lib/*" AWSUpdater.awsUpdater

I notice that the class awsUpdater is under the package AWSUpdater, so you can not use java -cp "../../../../lib/*" awsUpdater directly.
For Example:
I create a project like this:
|-test
|-AWSUpdater
|-awsUpdater.java
Detail of the awsUpdater.java:
public class awsUpdater {
public static void main(String[] args) {
System.out.println("hello");
}
}
then(now I'm in test/AWSUpdater):
javac awsUpdater.java
java awsUpdater
Everything goes well!
If I add the class to the package, like this:
package AWSUpdater;
public class awsUpdater {
public static void main(String[] args) {
System.out.println("hello");
}
}
then(now I'm in test/AWSUpdater):
javac awsUpdater.java
java awsUpdater
here, it will got the error which is same with yours.
Now, you can go to the package's root dir. (here is test), and then:
javac AWSUpdater/awsUpdater.java
java AWSUpdater/awsUpdater
Now, you will get the correct result.

html2image configuration in java

I would to ask about html2image, i have some codes like this
import gui.ava.html.image.generator.HtmlImageGenerator;
import java.io.File;
public class html2image {
public static void main(String[] args) {
HtmlImageGenerator imageGenerator = new HtmlImageGenerator();
imageGenerator.loadHtml("<b>Hello World!</b> Please goto <a title=\"Goto Google\" href=\"http://www.google.com\">Google</a>.");
imageGenerator.saveAsImage("hello-world.png");
imageGenerator.saveAsHtmlWithMap("hello-world.html", "hello-world.png");
}
}
But seems like after i call this java, its not appear any image or output image, maybe i miss some configuration, anyone can help ?

Try to give the absolute path in imageGenerator.saveAsImage as otherwise the file will be generated in the working directory.

How to download an online file directory (localhost) using Java

I have a static file server at "localhost:8888/fileserver".
I am trying to write a program in java to download the files from the server. The file server consists of three folders, therefore I am trying to write a script that automatically goes through the directory and copies it to my computer.
I know there is a wget function for linux that accomplishes this recursively. Is there a way to do this in Java?
Please could you advise on how I should go about doing this or proceed.
Thank you

Below is a code to go through an online directory and return back all the links needed to download.
After that I just need to download each individual link.
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
public class WebCrawler {
//Created a global list variable to save the links
static List<String> createList = new ArrayList<String>();
public static void main(String[] args) throws IOException {
String url = "http://localhost:8888";
System.out.println(myCrawler(url)+"\n"+"Size: "+myCrawler(url).size());
}
public static List<String> myCrawler(String url) throws IOException{
//Creates an open connection to a link
Document doc = Jsoup.connect(url).ignoreContentType(true).get();
Elements links = doc.select("a[href]");
//Recursively iterates through all the links provided on the initial url
for (Element i : links) {
String link = print("%s", i.attr("abs:href"));
if (link.endsWith("/")){myCrawler(link);} //Recursive part, calls back on itself
else {createList.add(link);}
}
return createList;
}
//Translates the link into a readable string object
private static String print(String msg, Object... args){return String.format(msg, args);}
}

Managing files in Java

I know C++ at a decent level and I am trying to learn java. This will be a silly question but I cannot figure out how to import a .java file into another. I am at Eclipse IDE and in my project I have two files:
FileReader.java
Entry.java
I want to import the Entry.java in the other file but no matter what I do I get an error. Can you help me? Thx in advance.
FileReader.java :
import java.io.*;
class FileReader {
public static void main(String[] args) throws Exception {
System.out.println("Hello, World");
Entry a(10,"a title","a description");
a.print();
}
}
Entry.java:
public class Entry{
int ID;
String title;
String description;
public Entry(int id, String t,String d){
ID=id;
title=t;
description=d;
}
public void print(){
System.out.println("ID:"+ID);
System.out.println("Title:"+title);
System.out.println("Description:"+description);
}
}
At this state I get an error that Entry cannot be resolved as a variable. So I believe that it is related to the import.

Firstly
Entry a(10,"a title","a description");
should be
Entry a = new Entry (10,"a title","a description");
If Entry is in the same package then you will not need to import it.
If Entry is in a different package, say com.example then you will need to do
Either
import com.example.Entry;
or
import com.example.*;
The second import will import all classes in the com.example package - usually not such a good thing.

You need new Entry
The new keyword creates the new object
Entry a = new Entry(10,"a title","a description")
a.print();
An Entry object is created with the a reference with the above instantiation.
For the import part of your question, if two files are in the same package, no import is needed. If you Entry class was in a different package than your FileReader class, then you would need to import mypackage.Entry

Try
Entry a = new Entry(/*args*/);
And if you need to import the class, then use the absolute name (package+class) and put it after import above the class declaration
import com.example.you.Entry;

In Eclipse you can do Ctrl+Shift+O to resolve all imports.

Error: Could not find or load main class- Novice

Hi I am a novice in JAVA. I have been getting this file not found exception inspite of the file existing in the very location I have specified in the path which is
Initially I had the issue of file not found. However, after performing a clean and re-run, now I am having an issue which says
Error: Could not find or load main class main.main
import Message.*;
import java.util.*;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.PrintWriter;
public class main{
public static void main(String[] args) {
Message msg=new Message("bob","alice","request","Data####");
MPasser passerObj=new MPasser("C:\\Workspace\\config.txt","process1");
}
}
Also in the MPasser Constructor the following piece of relevant code is there
public class MPasser(String file_name,String someVariable){
InputStream input;
try {
input =new RandomAccessFile(file_name,"r");
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Yaml yaml = new Yaml();
Map<String, String> Object = (Map<String, String>) yaml.load(input);
}
Sorry I have made edits from initial query so that it is more clear

On this line:
input = RandomAccessFile("C:\Workspace\conf.txt",'r');
You need to escape the \'s
input = RandomAccessFile("C:\\Workspace\\conf.txt",'r');

"C:\Workspace\conf.txt"
Those are escape sequences. You probably meant:
"C:\\Workspace\\conf.txt"
You also appear to call it config.txt in one snippet and conf.txt in the other?

Make sure the java process has permissions to read the file.

You have to escape the backslash.
input = RandomAccessFile("C:\\Workspace\\conf.txt",'r');
and also
input = new RandomAccessFile("C:\\Workspace\\conf.txt",'r');
and why you have two different filename conf.txt and config.txt.