How to load external properties file with Java without rebuilding the Jar? - java

I use gradle which structures projects in maven style so I have the following
src/main/java/Hello.java and src/main/resources/test.properties
My Hello.java look like this
public class Hello {
public static void main(String[] args) {
Properties configProperties = new Properties();
ClassLoader classLoader = Hello.class.getClassLoader();
try {
configProperties.load(classLoader.getResourceAsStream("test.properties"));
System.out.println(configProperties.getProperty("first") + " " + configProperties.getProperty("last"));
} catch (IOException e) {
e.printStackTrace();
}
}
}
This works fine. however I want to be able to point to .properties file outside of my project and I want to it to be flexible enough that I can point to any location without rebuilding the jar every time. Is there a way to this without using a File API and passing file path as an argument to the main method?

You can try this one, which will first try to load properties file from project home directory so that you don't have to rebuild jar, if not found then will load from classpath
public class Hello {
public static void main(String[] args) {
String configPath = "test.properties";
if (args.length > 0) {
configPath = args[0];
} else if (System.getenv("CONFIG_TEST") != null) {
configPath = System.getenv("CONFIG_TEST");
}
File file = new File(configPath);
try (InputStream input = file.exists() ? new FileInputStream(file) : Hello.class.getClassLoader().getResourceAsStream(configPath)) {
Properties configProperties = new Properties();
configProperties.load(input);
System.out.println(configProperties.getProperty("first") + " " + configProperties.getProperty("last"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
You can send the properties file path as argument or set the path to an environment variable name CONFIG_TEST

Archaius may be complete overkill for such a simple problem, but it is a great way to manage external properties. It is a library for handling configuration: hierarchies of configuration, configuration from property files, configuration from databases, configuration from user defined sources. It may seem complicated, but you will never have to worry about hand-rolling a half-broken solution to configuration again. The Getting Started page has a section on using a local file as the configuration source.

Related

Properties file not loading and updating for relative path but working fine for absolute path

I am trying to access a properties file from the src/main/resources folder but when I try to load the file using a relative path it is not getting updated. But it is working fine for an absolute path.
I need the dynamic web project to work across all platforms.
public static void loadUsers() {
try(
FileInputStream in = new FileInputStream("C:\\Users\\SohamGuha\\Documents\\work-coding\\work-coding\\src\\main\\resources\\users.properties")) {
// write code to load all the users from the property file
// FileInputStream in = new FileInputStream("classpath:users.properties");
users.load(in);
System.out.println(users);
in.close();
}
catch(Exception e){
e.printStackTrace();
}
First of all you are using Spring, at least that is what the tags at the bottom say. Secondly C:\\Users\\SohamGuha\\Documents\\work-coding\\work-coding\\src\\main\\resources\\users.properties is the root of your classpath. Instead of loading a File use the Spring resource abstraction.
As this is part of the classpath you can simply use the ClassPathResource to obtain a proper InputStream. This will work regardless of which environment you are in.
try( InputStream in = new ClassPathResource("users.properties").getInputStream()) {
//write code to load all the users from the property file
//FileInputStream in = new FileInputStream("classpath:users.properties");
users.load(in);
System.out.println(users);
} catch(Exception e){
e.printStackTrace();
}
NOTE: you are already using a try with resources so you don't need to close the InputStream that is already handled for you.
Changing things inside your application simply won't work, as this would mean you could change resources (read classes) in your jar which would be quite a security risk! If you want something to be changable you will have to make it a file outside of the classpath and directly on the file-system.
Try the following code
import java.io.FileInputStream;
import java.io.IOException;
public class LoadUsers {
public static void main(String[] args) throws IOException {
try(FileInputStream fis=new FileInputStream("src/main/resources/users.properties")){
Properties users=new Properties();
users.load(fis);
System.out.println(users);
}catch(IOException ioe) {
ioe.printStackTrace();
}
}
}

How to read application.properties file without Environment

Please can you help me to read the properties from application.properties file in Spring Boot, without autowiring the Environment and without using the Environment?
No need to use ${propname} either. I can create properties object but have to pass my properties file path. I want to get my prop file from another location.
This is a core Java feature. You don't have to use any Spring or Spring Boot features if you don't want to.
Properties properties = new Properties();
try (InputStream is = getClass().getResourceAsStream("application.properties")) {
properties.load(is);
}
JavaDoc: http://docs.oracle.com/javase/8/docs/api/java/util/Properties.html
OrangeDog solution didn't work for me. It generated NullPointerException.
I've found another solution:
ClassLoader loader = Thread.currentThread().getContextClassLoader();
Properties properties = new Properties();
try (InputStream resourceStream = loader.getResourceAsStream("application.properties")) {
properties.load(resourceStream);
} catch (IOException e) {
e.printStackTrace();
}
Try to use plain old Properties.
final Properties properties = new Properties();
properties.load(new FileInputStream("/path/config.properties"));
System.out.println(properties.getProperty("server.port"));
In case you need to use that external properties file in your configuration it can be accomplished with #PropertySource("/path/config.properties")
The following code extracts the environment value from an existing application.properties file which is located in the Deployed Resources under WEB-INF/classes :
// Define classes path from application.properties :
String environment;
InputStream inputStream;
try {
// Class path is found under WEB-INF/classes
Properties prop = new Properties();
String propFileName = "com/example/project/application.properties";
inputStream = getClass().getClassLoader().getResourceAsStream(propFileName);
// read the file
if (inputStream != null) {
prop.load(inputStream);
} else {
throw new FileNotFoundException("property file '" + propFileName + "' not found in the classpath");
}
// get the property value and print it out
environment = prop.getProperty("environment");
System.out.println("The environment is " + environment);
} catch (Exception e) {
System.out.println("Exception: " + e);
}
Here is example, running the above code with the following input from the application.properties (Text file):
# Application settings file
environment=Test
release_date=DATE
session_timeout_minutes=25
## Allowable image types
img_file_extensions="jpeg;pjpeg;jpg;png;gif"
## Images are saved with this extension
img_default_extension=jpg
# Mail Settings / Addresses
mail_debug=false
Output:
The environment is Test
To read application.properties just add this annotation to your class:
#ConfigurationProperties
public class Foo {
}
If you want to change the default file
#PropertySource("your properties path here")
public class Foo {
}
If everything else is properly set, you can the annotation #Value. Springboot will take care of loading the value from property file.
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.beans.factory.annotation.Value;
#Configuration
#PropertySource("classpath:/other.properties")
public class ClassName {
#Value("${key.name}")
private String name;
}
Adding to Vladislav Kysliy's elegant solution, below code can be directly plugged as REST API Call to get all the key/value of application.properties file in Spring Boot without knowing any key. Additionally, If you know the Key you can always use #Value annotation to find the value.
#GetMapping
#RequestMapping("/env")
public java.util.Set<Map.Entry<Object,Object>> getAppPropFileContent(){
ClassLoader loader = Thread.currentThread().getContextClassLoader();
java.util.Properties properties = new java.util.Properties();
try(InputStream resourceStream = loader.getResourceAsStream("application.properties")){
properties.load(resourceStream);
}catch(IOException e){
e.printStackTrace();
}
return properties.entrySet();
}

File not reading in selenium - maven framewaork

I tried to create a quick framework. in that I created below-mentioned classes:
Config file(All browsers path)
configDataProvider java class(reads the above file)
BrowserFactory class(has firefox browser object)
configDataProviderTest class(access data from dconfigDataProvider class)
now its not reading the paths mentioned in config.properties file.
I have provided all correct path and attached screenshots:
Looks like a problem is at your ConfigDataProvider class.
Firstly, you using Maven for building your project. Maven has defined project structure for code sources and for resources:
/src/main/java
/src/main/resorces
Thus, much better to put your .properties file there.
Second, you don't need to set the full path to your config file.
Relative path will be just enough. Something like below:
public class PropertiesFileHandler {
private static Logger log = Logger.getLogger(PropertiesFileHandler.class);
public static final String CONFIG_PROPERTIES = "src/main/resources/config.properties";
public static final String KEY = "browser.type";
public static BrowserType readBrowserType() {
BrowserType browserType = null;
Properties properties = new Properties();
try (InputStream inputStream = new BufferedInputStream(new FileInputStream(CONFIG_PROPERTIES))) {
properties.load(inputStream);
browserType = Enum.valueOf(BrowserType.class, properties.getProperty(KEY));
} catch (FileNotFoundException e) {
log.error("Properties file wasn't found - " + e);
} catch (IOException e) {
log.error("Problem with reading properties file - " + e);
}
return browserType;
}
}
Lastly, if you are building framework you don't need to put everything under src/main/test. This path specifies tests with future possibilities to be executed with maven default lifecycle - mvn test.
The core of your framework can look like:
Two things which I noticed:
Don't give path in your properties path within ""
all the path seperators should be replaced with double backward slash \\ or single forward slash /

How do you access .properties files inside an AppEngine app?

I've got an AppEngine app with two different instances, one for prod and one for staging. Accordingly, I'd like to configure the staging instance slightly differently, since it'll be used for testing. Disabling emails, talking to a different test backend for data, that kind of thing.
My first intuition was to use a .properties file, but I can't seem to get it to work. I'm using Gradle as a build system, so the file is saved in src/main/webapp/WEB-INF/staging.properties (and a matching production.properties next to it). I'm trying to access it like so:
public class Config {
private static Config sInstance = null;
private Properties mProperties;
public static Config getInstance() {
if (sInstance == null) {
sInstance = new Config();
}
return sInstance;
}
private Config() {
// Select properties filename.
String filename;
if (!STAGING) { // PRODUCTION SETTINGS
filename = "/WEB-INF/production.properties";
} else { // DEBUG SETTINGS
filename = "/WEB-INF/staging.properties";
}
// Get handle to file.
InputStream stream = this.getClass().getClassLoader().getResourceAsStream(filename);
if (stream == null) {
// --> Crashes here. <--
throw new ExceptionInInitializerError("Unable to open settings file: " + filename);
}
// Parse.
mProperties = new Properties();
try {
mProperties.load(stream);
} catch (IOException e) {
throw new ExceptionInInitializerError(e);
}
}
The problem is that getResourceAsStream() is always returning null. I checked the build/exploded-app directory, and the .properties file shows up there. I also checked the .war file, and found the .properties file there as well.
I've also tried moving the file into /WEB-INF/classes, but that didn't make a difference either.
What am I missing here?
Try
BufferedReader reader = new BufferedReader(new FileReader(filename));
or
InputStream stream = this.getClass().getResourceAsStream(filename);

Reading Properties file inside conf folder

I have a properties file which is located under conf folder. conf folder is under the project root directory. I am using the following code.
public class PropertiesTest {
public static void main(String[] args) {
InputStream inputStream = PropertiesTest.class
.getResourceAsStream("/conf/sampleprop.conf");
Properties prop = new Properties();
try {
prop.load(inputStream);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println(prop.getProperty("TEST"));
}
}
But I get nullpointer exception.
I have tried using
InputStream inputStream = PropertiesTest.class
.getResourceAsStream("./conf/sampleprop.conf");
and
InputStream inputStream = PropertiesTest.class
.getResourceAsStream("conf/sampleprop.conf");
But all result in nullpointer exception.
Can anyone please help.
Thanks in advance
Try to recover your working directory first:
String workingDir = System.getProperty("user.dir");
System.out.println("Current working dir: " + workingDir);
and then is simple:
Properties propertiesFile = new Properties();
propertiesFile.load(new FileInputStream(workingDir+ "/yourFilePath"));
String first= propertiesFile.getProperty("myprop.first");
Regards, fabio
The getResourceAsStream() method tries to locate and load the resource using the ClassLoader of the class it is called on. Ideally it can locate the files only the class folders .. Rather you could use FileInputStream with relative path.
EDIT
if the conf folder is under src, then you still be able to access with getResourceAsStream()
InputStream inputStream = Test.class
.getResourceAsStream("../conf/sampleprop.conf");
the path would be relative to the class from you invoke getRes.. method.
If not
try {
FileInputStream fis = new FileInputStream("conf/sampleprop.conf");
Properties prop = new Properties();
prop.load(fis);
System.out.println(prop.getProperty("TEST"));
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
NOTE: this will only work if it is Stand alone application/in eclipse. This will not work if its web based (as the root will be Tomcat/bin, for eg)
I would suggest to copy the configuration file at designated place, then you can acess at ease. At certain extent 'System.getProperty("user.dir")' can be used if you are always copying the file 'tomcat` root or application root. But if the files to be used by external party, ideal to copy in a configurable folder (C:\appconf)
Your code works like a charm! But you might have to add the project root dir to your classpath.
If you work with Maven, place your configuration in src/main/resources/conf/sampleprop.conf
When invoking java directly add the project root dir with the java -classpath parameter. Something like:
java -classpath /my/classes/dir:/my/project/root/dir my.Main

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