Unable to read properties file after creating it - java

I am creating a properties file and putting into my classpath folder Resources.
When I tried to read this file , i am not getting the expected result. i am getting the result of the previous values printed instead of the property values set now.
My class file is as follows :
public class App {
public static void main(String[] args) {
Properties prop = new Properties();
PrintWriter output = null;
try {
output = new PrintWriter("Resources/config.properties");
// set the properties value
prop.setProperty("database", "localhost");
prop.setProperty("dbuser", "mkyong");
prop.setProperty("dbpassword", "password");
// save properties to project root folder
prop.store(output, null);
if(output!=null) {
System.out.println("Output");
output.close();
}
} catch (IOException io) {
io.printStackTrace();
} finally {
if (output != null) {
output.close();
}
}
Properties prop1 = new Properties();
BufferedInputStream input = null;
try {
String filename = "config.properties";
input = (BufferedInputStream) AppCPLoad.class.getClassLoader().getResourceAsStream(filename);
if(input==null){
System.out.println("Sorry, unable to find " + filename);
return;
}
//load a properties file from class path, inside static method
prop1.load(input);
//get the property value and print it out
System.out.println(prop1.getProperty("database"));
System.out.println(prop1.getProperty("dbuser"));
System.out.println(prop1.getProperty("dbpassword"));
if(input!=null) {
System.out.println("Input");
input.close();
}
} catch (IOException ex) {
ex.printStackTrace();
} finally{
if(input!=null){
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
Please help.

When you run the program, the properties file is loaded and the values are read. After you rewrite the properties file, that doesn't mean that the properties you have loaded already have be to rewritten. You need to reload the properties file and re-read the values. You are looking for an implementation like ReloadableResourceBundleMessageSource

Related

Propert file is not loading properly

Getting NullPointerException when running all my script in the middle. I have xpath written in the property file and I'm loading the property file in BeforeSuite. The element will be present and the page is also present. Getting null in locator.
may be your property file is not giving the exact value of you element.
try calling this function by providing the property name.
public static String getProperty(String propertyname)
{
Properties prop = new Properties();
InputStream input = null;
try {
input = new FileInputStream(("path of your property file"));
// load a properties file
prop.load(input);
} catch (IOException ex) {
ex.printStackTrace();
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
System.out.println(prop.getProperty(propertyname));
//Return the property value
return prop.getProperty(propertyname);
}

Text document is becoming file folder

Here is my class, what I am doing wrong. Why is my text document becoming a file folder. Please explain what is going on and how I can correct it. Thank you
public class InputOutput {
public static void main(String[] args) {
File file = new File("C:/Users/CrypticDev/Desktop/File/Text.txt");
Scanner input = null;
if (file.exists()) {
try {
PrintWriter pw = new PrintWriter(file);
pw.println("Some data that we have stored");
pw.println("Another data that we stored");
pw.close();
} catch(FileNotFoundException e) {
System.out.println("Error " + e.toString());
}
} else {
file.mkdirs();
}
try {
input = new Scanner(file);
while(input.hasNext()) {
System.out.println(input.nextLine());
}
} catch(FileNotFoundException e) {
System.out.println("Error " + e.toString());
} finally {
if (input != null) {
input.close();
}
}
System.out.println(file.exists());
System.out.println(file.length());
System.out.println(file.canRead());
System.out.println(file.canWrite());
System.out.println(file.isFile());
System.out.println(file.isDirectory());
}
}
Thanks. The above is my Java class.
You mistakingly assume Text.txt is not a directory name.
mkdirs() creates a directory (and all directories needed to create it). In your case 'Text.txt'
See here: https://docs.oracle.com/javase/7/docs/api/java/io/File.html#mkdirs().
It is perfectly fine for a directory to have a . in it.
You could use getParentFile() to get the directory you want to create and use mkdirs() on that.
For additional informations. Here is the différence between the two representaions of files and directories:
final File file1 = new File("H:/Test/Text.txt"); // Creates NO File/Directory
file1.mkdirs(); // Creates directory named "Text.txt" and its parent directory "H:/Test" if it doesn't exist (may fail regarding to permissions on folders).
final File file = new File("H:/Test2/Text.txt"); // Creates NO File/Directory
try {
file.createNewFile(); // Creates file named "Text.txt" (if doesn't exist) in the folder "H:/Test2". If parents don't exist, no file is created.
} catch (IOException e) {
e.printStackTrace();
}
Replace your code:
else {
file.mkdirs();
}
with:
else {
if (!file.isFile()&&file.getParentFile().mkdirs()) {
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
}

Java eclipse error with exported runnable jar file

I have a problem with an exported jar file. When I run my project in Eclipse it runs fine, but when I run it as an exported jar from the console I receive the following error message:
java.io.FileNotFoundException: firstLaunch.properties (System can't find file)
or
java.io.FileNotFoundException: resources/config/firstLaunch.properties (System can't find file)
I tried to put it in to the resource folder and change syntax from firstLaunch.properties to /resource/config/firstLaunch.properties, but again it says the same thing but with a different path. I don't know why is this doing this.
Here is the code:
public void saveConfigFile(String file, String key, String value) {
Properties prop = new Properties();
OutputStream output = null;
try {
output = new FileOutputStream(file);
// set the properties value
prop.setProperty(key, value);
// save properties to project root folder
prop.store(output, null);
} catch (IOException io) {
io.printStackTrace();
} finally {
if (output != null) {
try {
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
My syntax for executing the method is
if (properties.loadConfigFile("firstLaunch.properties", "value").equals(properties.loadConfigFile("true.properties", "true"))) {
properties.saveConfigFile("port.properties", "port", "8795");
properties.saveConfigFile("ip.properties", "ip", temp[1]);
properties.saveConfigFile("firstLaunch.properties", "value", "false");
settings.port = properties.loadConfigFile("port.properties", "port");
settings.myIp = properties.loadConfigFile("ip.properties", "ip");
} else {
settings.port = properties.loadConfigFile("port.properties", "port");
settings.myIp = properties.loadConfigFile("ip.properties", "ip");
}
Your problem probably has to do with how you are referencing the file location. Add some detail/code examples as to how you are referencing the code, so then we can be sure to help. Having said that here is another way to reference a properties file:
Put it in the classpath like this:
private static Properties prop = new Properties();
private static String filename = "<name of file>.properties";
InputStream input = <ClassName>.class.getClassLoader().getResourceAsStream(filename);
try {
if (input==null) {
loggerOut.log(Level.SEVERE, "Sorry, unable to find " + filename);
}
prop.load(input);
loggerOut.info("XML In storage path: " prop.getProperty("<property in file>"));
fileNameAndPath = prop.getProperty("fileNameAndPathIN").trim();
logNameAndPath = logPath + logName;
} catch (IOException ex) {
ex.printStackTrace();
} finally {
if (input!=null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

save a created propertyfile in specific folder

How can I save a prop file in a specific folder for example,
now it is saved in the root I guess, but it needs to be in the same folder as the class where it is created.
I also want to know how to load it. If it possible to load a properties file easily from the root then it is okay as well to save it in the root.
code creating the file, first 2 lines with // ( = make code work now without using prop file), class name = Providers
public static DataAccessProvider createProvider (URL url) {
//MovieDAOOnline mdaoOn = new MovieDAOOnline();
//mdaoOn.setUrl(url);
Properties prop = new Properties();
OutputStream output = null;
try {
output = new FileOutputStream("config.properties");
// set the properties value
prop.setProperty("uri", url.toString());
prop.store(output, null);
} catch (IOException io) {
io.printStackTrace();
} finally {
if (output != null) {
try {
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return new OnlineProvider();
}
code for getting the file, first line in comment needs to be changed to get uri from propertie:
public Movie getMovie(int id) throws DataAccessException{
//StringBuilder builder = new StringBuilder(url.toString());
builder.append("movies.xml");
MovieConfigRead mcr = new MovieConfigRead();
List<Movie> film = null;
try {
film = mcr.geefMovies(builder.toString());
} catch (JAXBException e) {
throw new DataAccessException();
} catch (MalformedURLException e) {
throw new DataAccessException();
}
for (Movie movie : film) {
if (movie.getId() == id) {
return movie;
}
}
return null;
}

Update properties file values with form values

I am having a jsp file in which I load the existing values present in properties file. When the user edit the existing value and submit the form, the properties file must be updated with that values. Can anyone help me with this? I am using only java.
FileInputStream in = new FileInputStream("Example.properties");
Properties props = new Properties();
props.load(in);
Now Update it
FileOutputStream outputStream = new FileOutputStream("Example.properties");
props.setProperty("valueTobeUpdate", "new Value");
props.store(outputStream , null);
outputStream .close();
Another way of achieving same is explained at
http://crunchify.com/java-properties-files-how-to-update-config-properties-file-in-java/
PropertiesConfiguration config = new PropertiesConfiguration("/Users/abc/Documents/config.properties");
config.setProperty("Name", "abcd");
config.setProperty("Email", "abcd#gmail.com");
config.setProperty("Phone", "123456");
config.save();
here is an example of how to update your properties file :
public class PropertyManager {
private static Properties prop = new Properties();
private static String PROPERTY_FILENAME = "config.properties";
public static void main(String[] args) {
loadProperty();
System.out.println(prop.get("myProperty"));
updateProperty("myProperty", "aSecondValue");
}
public static void loadProperty(){
InputStream input = null;
try {
input = new FileInputStream(PROPERTY_FILENAME);
// load a properties file
prop.load(input);
} catch (IOException ex) {
ex.printStackTrace();
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
public static void updateProperty(String name, String value){
OutputStream output = null;
try {
output = new FileOutputStream(PROPERTY_FILENAME);
// set the properties value
prop.setProperty(name, value);
// save properties to project root folder
prop.store(output, null);
} catch (IOException io) {
io.printStackTrace();
} finally {
if (output != null) {
try {
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
I let you change "new Properties", by the way you retrieve it.

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