How to avoid the java FileNotFoundException when loading resources?

14/11/202214/11/2022 | Sarah HendricksonSarah Hendrickson | 0 Comment | 12:00 am

How to avoid the java FileNotFoundException when loading resources?

Resources

getResourceAsStream() looks at the classpath for the given resource. The leading slash on the input to getResourceAsStream() tells the loader to read from the base of the classpath. The contents of our JAR file are on the classpath, so this method works.

How do I use ClassPathResource?

2. Using Resource

  1. 2.1. Manually. For accessing a resource from the classpath, we can simply use ClassPathResource: public Resource loadEmployeesWithClassPathResource() { return new ClassPathResource(“data/employees.dat”); }
  2. 2.2. Using @Value. We can also inject a Resource with @Value:
  3. 2.3. Using ResourceLoader.

How do I handle Java IO FileNotFoundException?

How to Fix FileNotFoundException. Since FileNotFoundException is a checked exception, a try-catch block should be used to handle it. The try block should contain the lines of code that can throw the exception and the catch block should catch and handle the exception appropriately.

What is default classpath in spring boot?

By default Spring Boot will serve static content from a directory called /static (or /public or /resources or /META-INF/resources) in the classpath.

What is ClassPathResource in spring?

ClassPathResource
ClassPathResource is a Resource implementation for class path resources. It supports resolution as java. io. File if the class path resource resides in the file system, but not for resources in a JAR.

How do I add a resource file to a JAR file?

1) click project -> properties -> Build Path -> Source -> Add Folder and select resources folder. 2) create your JAR!

What is a ClassPathResource?

ClassPathResource is a Resource implementation for class path resources. It supports resolution as java. io. File if the class path resource resides in the file system, but not for resources in a JAR. To read a file inside a jar or war file, please use resource.

How do I read a classpath file?

Place the directory of file ( D:\myDir )in CLASSPATH and try below: InputStream in = this. getClass(). getClassLoader().
…

  1. The file path isn’t any use if the resource is in a JAR or WAR file.
  2. The getFile method of URL does not return a file name.

What cases are in FileNotFoundException?

FileNotFoundException is thrown by constructors of FileInputStream, FileOutputStream, RandomAccessFile when file is not found on specified path. Exception can also be raised when file is inaccessible for some reason. For example: When you do not have proper permissions to read the files.

How do I combine two exceptions in Java?

Java Catch Multiple Exceptions
A try block can be followed by one or more catch blocks. Each catch block must contain a different exception handler. So, if you have to perform different tasks at the occurrence of different exceptions, use java multi-catch block.

What is ClassPathResource in Spring?

What is the difference between path and classpath?

The main difference between PATH and CLASSPATH is that Path is set for java tools in java programs like java and javac, which are used to compile your code. Whereas CLASSPATH is used by System or Application class loader to locate and load compile Java bytecodes stored in the . class file.

How do I read a JSON file from resources in Spring boot?

“spring boot read json file from resources folder” Code Answer

  1. public void testResourceFile() throws IOException {
  2. File resource = new ClassPathResource(“test.json”). getFile();
  3. String text = new String(Files. readAllBytes(resource. toPath()));

How do I map a URL in Spring?

Try a URL − http://localhost:8080/TestWeb/helloWorld.htm and we will see the following screen, if everything is fine with the Spring Web Application. Try a URL http://localhost:8080/TestWeb/welcome.htm and you should see the following result if everything is fine with your Spring Web Application.

How do I view resources in a jar file?

To access a file in a jar you have two options:

  1. Place the file in directory structure matching your package name (after extracting . jar file, it should be in the same directory as .
  2. Place the file at the root (after extracting . jar file, it should be in the root), then access it using Thread.

How do I view files in a jar file?

How do I open a Java JAR file?

  1. Change the extension of the JAR file from . jar to . zip.
  2. Right-click on the JAR file and select Extract All.
  3. View the contents of the open JAR file on the file system.

What is ClassPathResource in Java?

How do you set classpath?

GUI:

  1. Select Start.
  2. Go to the Control Panel.
  3. Select System and Security.
  4. Select Advanced System settings.
  5. Click on Environment Variables.
  6. Click on New under System Variables.
  7. Add CLASSPATH as variable name and path of files as a variable value.
  8. Select OK.

How do I check FileNotFoundException?

How to resolve FileNotFoundException

  1. Check if passed file is present in specified file.
  2. Check if passed file is actually directory.
  3. The passed file can not be open due to permission issues.
  4. Check if passed file name does not contain any invisible characters such as \r\n symbols.

How does FileNotFoundException work?

Class FileNotFoundException
Signals that an attempt to open the file denoted by a specified pathname has failed. This exception will be thrown by the FileInputStream , FileOutputStream , and RandomAccessFile constructors when a file with the specified pathname does not exist.

How do you handle two exceptions in single catch?

Java allows you to catch multiple type exceptions in a single catch block. It was introduced in Java 7 and helps to optimize code. You can use vertical bar (|) to separate multiple exceptions in catch block. An old, prior to Java 7 approach to handle multiple exceptions.

Can we throws multiple exceptions in Java?

You can’t throw two exceptions. I.e. you can’t do something like: try { throw new IllegalArgumentException(), new NullPointerException(); } catch (IllegalArgumentException iae) { // }

Is it mandatory to set classpath in Java?

We don’t need to set PATH and CLASSPATH to compile and run java program while using IDE like Eclipse. These environment variables are required to compile and run java program using CMD. Compiling the program- I have java program file Demo. java stored at location D:\Programs\Classes .

Is it necessary to set classpath in Java?

Java Compiler and JVM (Java Virtual Machine) use CLASSPATH to locate the required files. If the CLASSPATH is not set, Java Compiler will not be able to find the required files and hence will throw the following error.

How do I read JSON properties in spring boot?

Load Spring Boot Properties From a JSON File

  1. Introduction.
  2. Loading Properties in Spring Boot.
  3. Load Properties via Command Line.
  4. Load Properties via PropertySource Annotation.
  5. Using PropertySourceFactory to Parse JSON.
  6. Using a Custom ContextInitializer.
  7. Conclusion.

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