I downloaded apache commons FileUtils to perform a copy directory and added them under libraries in eclipse as well. When I say Fileutils.copyDirectory(s,d) as give below eclipse says " Multiple markers at this line -Syntax error on token "(", delete this token
-Syntax error on token ")", delete this token". Can someone help
import org.apache.commons.io.FileUtils;
Public class b {
File s = new file("C://Tom//eso");
File d = new file("C://Tom//pos");
FileUtils.copyDirectory(s,d);
}
Try this:
import org.apache.commons.io.FileUtils;
public class B {
public static void main(String[] args) throws Exception {
File s = new File("C:/Tom/eso");
File d = new File("C:/Tom/pos");
FileUtils.copyDirectory(s,d);
}
}
There are several errors in your code:
Classes start with an uppercase char - it's File, not file. And it's class B, not class b (remember to also rename the file to B.java)
You must not use double / chars, just one
The code must reside inside a method, not at the class level
It's public, not Public
You're not handling exceptions, either throw them or catch them
File s = new file("C://Tom//eso");
File d = new file("C://Tom//pos");
file should be capitalized. It should be new File(....
Side note: Usually for windows the path looks like C:\\Tom\\eso, you have forward-slashes instead of backward.
You're trying to call a method outside of the body of a method...try something more along the lines of;
public class b {
public static void main(String args[]) {
File s = new File("C:/Tom/eso");
File d = new File("C:/Tom/pos");
try {
FileUtils.copyDirectory(s,d);
} catch (IOException exp) {
exp.printStackTrace();
}
}
}
Just to highlight...
Public should be public
file should be File
// should be either / or \\ (most people prefer /)
Execution code must be executed from the context of a method or static init section
I'd also recommend that you take the time to learn the Java naming conventions as well as have a read through the tutorials under the Trails Covering the Basics section
Two errors.
First
File s = new file("C://Tom//eso");
File d = new file("C://Tom//pos");
should be
File s = new File("C://Tom//eso");
File d = new File("C://Tom//pos");
Second
FileUtils.copyDirectory(s,d);
should in main method.
Related
I created a Locale setting so Italian, English, ... I needed to know how to set up a predefined config already: I have obviously tried how every good person does this but I think it is too inefficient, I also tried to create files through the IDE in the same location where the files in the DataFolder are created at the onEnable but obviously it didn't work, however what I tried to be ineffective is this: customConfig.set("Hi-Message", "I'm sorry, i love you");
The way I'm doing it right now, is simply having the config file in the source code itself and, if the file-version of the config does not exist yet, creates a new config file using the config file from the compiled source code.
In my onEnable method in Main, I simply call a method in another class FileManager.setup().
It looks a bit like this in setup():
public static void setup() throws IOException {
File plugin_work_directory = new File(plugin_work_path);
core_server_config = new File(plugin_work_path + "config.txt");
if (!plugin_work_directory.exists()) plugin_work_directory.mkdir();
if (!core_server_config.exists()) {
InputStream core_server_config_template = (Main.class.getResourceAsStream("/config.txt"));
Files.copy(core_server_config_template, Paths.get(plugin_work_path + "config.txt"));
}
Config.load();
if (Integer.parseInt(Config.getValue("config.version")) < Config.version) {
core_server_config.delete();
InputStream core_server_config_template = (Main.class.getResourceAsStream("/config.txt"));
Files.copy(core_server_config_template, Paths.get(plugin_work_path + "config.txt"));
}
Config.load();
}
Config.load() parses the values into a private hashmap of the Config class, whereby other classes can reference the hashmap through a String getValue(String string) method.
I have a small java program that reads a given file with data and converts it to a csv file.
I've been trying to use the arrow symbols: ↑, ↓, → and ← (Alt+24 to 27) but unless the program is run from within Netbeans (Using F6), they will always come out as '?' in the resulting csv file.
I have tried using the unicodes, eg "\u2190" but it makes no difference.
Anyone know why this is happening?
As requested, here is a sample code that gives the same issue. This wont work when run using the .jar file, just creating a csv file containing '?', however running from within Netbeans works.
import java.io.FileNotFoundException;
import java.io.PrintWriter;
public class Sample {
String fileOutName = "testresult.csv";
/**
* #param args the command line arguments
*/
public static void main(String[] args) throws FileNotFoundException {
Sample test = new Sample();
test.saveTheArrow();
}
public void saveTheArrow() {
try (PrintWriter outputStream = new PrintWriter(fileOutName)) {
outputStream.print("←");
outputStream.close();
}
catch (FileNotFoundException e) {
// Do nothing
}
}
}
new PrintWriter(fileOutName) uses the default charset of the JVM - you may have different defaults in Netbeans and in the console.
Google Sheet uses UTF_8 according to this thread so it would make sense to save your file using that character set:
Files.write(Paths.get("testresult.csv"), "←".getBytes(UTF_8));
Using the "<-" character in your editor is for sure not the desired byte 0x27.
Use
outputStream.print( new String( new byte[] { 0x27}, StandardCharsets.US_ASCII);
i am developing an simple blackberry application in BlackBerry - Java Plug-in for Eclipse. In that, i want to read data from an external text file. I had searched for this, and tried for some tips, like. But failed at last. I will describe my application...
my main file...
package com.nuc;
import net.rim.device.api.ui.UiApplication;
public class Launcher extends UiApplication
{
public static void main(String[] args)
{
Launcher theApp = new Launcher();
theApp.enterEventDispatcher();
}
public Launcher()
{
pushScreen(new MyScreen());
}
}
And then my app class is like....
package com.nuc;
import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.ui.component.BasicEditField;
import net.rim.device.api.ui.component.Dialog;
import net.rim.device.api.ui.component.EditField;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.container.GridFieldManager;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.FieldChangeListener;
public final class MyScreen extends MainScreen implements FieldChangeListener
{
// declared variables...
public MyScreen()
{
//rest codes...
I want to show some details from a text file before my app starts, like the End User License Agreement.. ie, something which cames as the first line..
my first question is, where i need to put that text file... i got lots of guidance from net, but nothing worked for eclipse..
Secondly, then how can i read the file and put its content in a dialog.
So plz guide me how i can achieve it.. sample code will be appreciable, for i am new to this environment...
To add a file to your Eclipe project
right click on the res folder of your project structure, click on New, click on Untitled Text File and then enter some text and save the file.
To read from a file and display on a dialog try something like the following code snippet:
try {
InputStream is = (InputStream) getClass().getResourceAsStream("/Text");
String str = "";
int ch;
while ((ch = is.read()) != -1) {
str += (char)ch;
}
synchronized (UiApplication.getEventLock()) {
Dialog.alert(str == null ? "Failed to read." : str);
}
} catch (Exception e) {
synchronized (UiApplication.getEventLock()) {
Dialog.alert(e.getMessage() + " + " + e.toString());
}
}
in the above code "/Text" is the file name. And if you got a NullPointerException then check the file name and path.
Rupak's answer is mostly correct, but there's a few problems with it. You definitely don't want to add immutable strings together in a situation like this. When you add 2 strings together (myString += "Another String") Java basically creates a new String object with the values of the two other Strings, because it cannot change the contents of the other strings. Usually this is fine if you just need to add two strings together, but in this case if you have a large file then you're creating a new String object for EVERY character in the file (each object bigger than the last). There's a lot of overhead associated with this object creation AND the garbage collector (very slow) will have to intervene more often because of all these objects that need to be destroyed.
StringBuffer to the rescue! Using a StringBuffer in place of the String concatenation will only require 1 object to be created and will be much faster.
try {
InputStream is = (InputStream) getClass().getResourceAsStream("/Text");
StringBuffer str = new StringBuffer();
int ch;
while ((ch = is.read()) != -1) {
str.append((char)ch);
}
UiApplication.getUiApplication().invokeLater(new Runnable(){
public void run(){
Dialog.alert(str.toString() == null ? "Failed to read." : str.toString());
}
}
} catch (Exception e) {
UiApplication.getUiApplication().invokeLater(new Runnable(){
public void run(){
Dialog.alert(e.getMessage() + " + " + e.toString());
}
}
}
Also several developers on the Blackberry support forums recommend against using UiApplication.getEventLock() because it can be "dangerous". They recommend using invokeLater() instead. See Blackberry Support Forums
Yes, the Internet says - "unzip them all, decompile and compare the code with some tool (total comander, WinCompare, meld(linux), whatever...) The reason why I need a tool to generate difference report automatically from Fodler1 and Folder2 is simple - there are too much JARs in these Folders and I need to compare these folders (with next version of Jars) say 1 time in a month. So, I really do not want to do it manually at all!
Let's see what I've got so far:
1) I can find all JARs in each Folder:)
2) I can get the list of classes from each JAR:
private static void AddAllClassesFromJAR(JarInputStream jarFile,
ArrayList<String> classes) throws IOException {
JarEntry jarEntry = null;
while (true) {
jarEntry = jarFile.getNextJarEntry();
if (jarEntry == null) {
break;
}
if (jarEntry.getName().endsWith(".class")) {
classes.add(jarEntry.getName());
}
}
}
public static List<String> getClasseNamesInPackage(String jarName) {
ArrayList<String> classes = new ArrayList<String>();
try {
JarInputStream jarFile = new JarInputStream(new FileInputStream(jarName));
AddAllClassesFromJAR(jarFile, classes);
} catch (Exception e) {
e.printStackTrace();
}
return classes;
}
3) There is Reflection in Java (Core Java 2 Volume I - Fundamentals, Example 5-5), so I can get the list of methods from one class once I know its name.
In order to do that I need to make an instance of each class, the problem is how can I make the instance of each Class which I got from each JAR file?
Now I'm loading each JAR:
loader_left = new JarClassLoader("left/1.jar");
public class JarClassLoader extends URLClassLoader {
public JarClassLoader( URL url ) {
super( new URL[]{url} );
}
public JarClassLoader( String urlString ) throws MalformedURLException {
this( new URL( "jar:file://" + urlString + "!/" ) );
}
No exceptions, but I can not find any resource in it, trying to load the class like:
class_left = loader_left.loadClass("level1.level2.class1");
And getting "java.lang.ClassNotFoundException".
Any glue where is the problem? (class name is verified. it is hardcoded just for testing, ideally it should get it from the list of the classes)
Second question: since most of the classes in Folder1 and Folder2 will be same, what will happen if I load the same class second time (from Fodler2)?
Try the jarcomp utility.
This is not directly answering your question, however you may get a look to the ASM framework . This allows you to analyze bytecode without having to load the classes with the class loader. It is probably easier to do it this way.
I have a bunch of strings in a properties file which i want to 'un-externalize', ie inline into my code.
I see that both Eclipse and Intellij have great support to 'externalize' strings from within code, however do any of them support inlining strings from a properties file back into code?
For example if I have code like -
My.java
System.out.println(myResourceBundle.getString("key"));
My.properties
key=a whole bunch of text
I want my java code to be replaced as -
My.java
System.out.println("a whole bunch of text");
I wrote a simple java program that you can use to do this.
Dexternalize.java
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map.Entry;
import java.util.Properties;
import java.util.Set;
import java.util.Stack;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Deexternalize {
public static final Logger logger = Logger.getLogger(Deexternalize.class.toString());
public static void main(String[] args) throws IOException {
if(args.length != 2) {
System.out.println("Deexternalize props_file java_file_to_create");
return;
}
Properties defaultProps = new Properties();
FileInputStream in = new FileInputStream(args[0]);
defaultProps.load(in);
in.close();
File javaFile = new File(args[1]);
List<String> data = process(defaultProps,javaFile);
buildFile(javaFile,data);
}
public static List<String> process(Properties propsFile, File javaFile) {
List<String> data = new ArrayList<String>();
Set<Entry<Object,Object>> setOfProps = propsFile.entrySet();
int indexOf = javaFile.getName().indexOf(".");
String javaClassName = javaFile.getName().substring(0,indexOf);
data.add("public class " + javaClassName + " {\n");
StringBuilder sb = null;
// for some reason it's adding them in reverse order so putting htem on a stack
Stack<String> aStack = new Stack<String>();
for(Entry<Object,Object> anEntry : setOfProps) {
sb = new StringBuilder("\tpublic static final String ");
sb.append(anEntry.getKey().toString());
sb.append(" = \"");
sb.append(anEntry.getValue().toString());
sb.append("\";\n");
aStack.push(sb.toString());
}
while(!aStack.empty()) {
data.add(aStack.pop());
}
if(sb != null) {
data.add("}");
}
return data;
}
public static final void buildFile(File fileToBuild, List<String> lines) {
BufferedWriter theWriter = null;
try {
// Check to make sure if the file exists already.
if(!fileToBuild.exists()) {
fileToBuild.createNewFile();
}
theWriter = new BufferedWriter(new FileWriter(fileToBuild));
// Write the lines to the file.
for(String theLine : lines) {
// DO NOT ADD windows carriage return.
if(theLine.endsWith("\r\n")){
theWriter.write(theLine.substring(0, theLine.length()-2));
theWriter.write("\n");
} else if(theLine.endsWith("\n")) {
// This case is UNIX format already since we checked for
// the carriage return already.
theWriter.write(theLine);
} else {
theWriter.write(theLine);
theWriter.write("\n");
}
}
} catch(IOException ex) {
logger.log(Level.SEVERE, null, ex);
} finally {
try {
theWriter.close();
} catch(IOException ex) {
logger.log(Level.SEVERE, null, ex);
}
}
}
}
Basically, all you need to do is call this java program with the location of the property file and the name of the java file you want to create that will contain the properties.
For instance this property file:
test.properties
TEST_1=test test test
TEST_2=test 2456
TEST_3=123456
will become:
java_test.java
public class java_test {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
}
Hope this is what you need!
EDIT:
I understand what you requested now. You can use my code to do what you want if you sprinkle a bit of regex magic. Lets say you have the java_test file from above. Copy the inlined properties into the file you want to replace the myResourceBundle code with.
For example,
TestFile.java
public class TestFile {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
public static void regexTest() {
System.out.println(myResourceBundle.getString("TEST_1"));
System.out.println(myResourceBundle.getString("TEST_1"));
System.out.println(myResourceBundle.getString("TEST_3"));
}
}
Ok, now if you are using eclipse (any modern IDE should be able to do this) go to the Edit Menu -> Find/Replace. In the window, you should see a "Regular Expressions" checkbox, check that. Now input the following text into the Find text area:
myResourceBundle\.getString\(\"(.+)\"\)
And the back reference
\1
into the replace.
Now click "Replace all" and voila! The code should have been inlined to your needs.
Now TestFile.java will become:
TestFile.java
public class TestFile {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
public static void regexTest() {
System.out.println(TEST_1);
System.out.println(TEST_1);
System.out.println(TEST_3);
}
}
You may use Eclipse "Externalize Strings" widget. It can also be used for un-externalization. Select required string(s) and press "Internalize" button. If the string was externalized before, it'll be put back and removed from messages.properties file.
May be if you can explain on how you need to do this, then you could get the correct answer.
The Short answer to your question is no, especially in Intellij (I do not know enough about eclipse). Of course the slightly longer but still not very useful answer is to write a plugin. ( That will take a list of property files and read the key and values in a map and then does a regular expression replace of ResourceBundle.getValue("Key") with the value from Map (for the key). I will write this plugin myself, if you can convince me that, there are more people like you, who have this requirement.)
The more elaborate answer is this.
1_ First I will re-factor all the code that performs property file reading to a single class (or module called PropertyFileReader).
2_ I will create a property file reader module, that iterates across all the keys in property file(s) and then stores those information in a map.
4_ I can either create a static map objects with the populated values or create a constant class out of it. Then I will replace the logic in the property file reader module to use a get on the map or static class rather than the property file reading.
5_ Once I am sure that the application performs ok.(By checking if all my Unit Testing passes), then I will remove my property files.
Note: If you are using spring, then there is a easy way to split out all property key-value pairs from a list of property files. Let me know if you use spring.
I would recommend something else: split externalized strings into localizable and non-localizable properties files. It would be probably easier to move some strings to another file than moving it back to source code (which will hurt maintainability by the way).
Of course you can write simple (to some extent) Perl (or whatever) script which will search for calls to resource bundles and introduce constant in this place...
In other words, I haven't heard about de-externalizing mechanism, you need to do it by hand (or write some automated script yourself).
An awesome oneliner from #potong sed 's|^\([^=]*\)=\(.*\)|s#Messages.getString("\1")#"\2"#g|;s/\\/\\\\/g' messages.properties |
sed -i -f - *.java run this inside your src dir, and see the magic.