resources | chobit

Reading files from a SpringBoot jar is something a little complex.

I had tried to read a file from springboot resources folder using java.io.File. This is the code:

public static void readFromResources() {
    String path = "config.xml";
    String fullPath = IoKit.class.getClassLoader().getResource(path).getFile();
    File file = new File(fullPath);
    System.out.println(file.exists());
}

public static void readFromResources() {

String path = "config.xml";

String fullPath = IoKit.class.getClassLoader().getResource(path).getFile();

File file = new File(fullPath);

System.out.println(file.exists());

}

And I got the FileNotFoundException :

java.io.FileNotFoundException: class path resource [config.xml] cannot be resolved to absolute file path because it does not reside in the file system: file:/data/www/htdocs/my-app/lib/my-app.jar!/BOOT-INF/class
es!/config.xml
        at org.springframework.util.ResourceUtils.getFile(ResourceUtils.java:217)
        at org.springframework.core.io.AbstractFileResolvingResource.getFile(AbstractFileResolvingResource.java:154)
        at org.chobit.IoKit.readResources(IoKit.java:46)
        at org.chobit.IoKitTest.readResources(IoKitTest.java:67)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
        at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:893)
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:798)
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)

java.io.FileNotFoundException: class path resource [config.xml] cannot be resolved to absolute file path because it does not reside in the file system: file:/data/www/htdocs/my-app/lib/my-app.jar!/BOOT-INF/class

es!/config.xml

at org.springframework.util.ResourceUtils.getFile(ResourceUtils.java:217)

at org.springframework.core.io.AbstractFileResolvingResource.getFile(AbstractFileResolvingResource.java:154)

at org.chobit.IoKit.readResources(IoKit.java:46)

at org.chobit.IoKitTest.readResources(IoKitTest.java:67)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:498)

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:893)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:798)

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)

Since there is no path like file:/data/www/htdocs/my-app/lib/my-app.jar!/BOOT-INF/class existed in my computer, I got the exception. Continue reading →

Maybe mvn clean package is one of the easiest operation in java programing. Howerver, I recently encountered a problem of packaging, which took up some of my time.

This was the initial package config in maven pom:

<resources>
    <resource>
        <directory>src/main/resources</directory>
        <filtering>true</filtering>
    </resource>
</resources>

<directory>src/main/resources</directory>

</resource>

</resources>

And this is the path of the file I wanted to package and read:

src/main/resources/template/xxx.xml

1	src/main/resources/template/xxx.xml

Executing the package command (mvn clean package) and opening the jar with compression software (e.g. WinRAR), the file was expected to locate at BOOT-INFO/class/template. However I could not find it. Though all files in resources folder directly existed, the others in subdirectories was not there. Continue reading →

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Tag Archives: resources

Reading files from SpringBoot resources folder

Package all files in Java resources’ subdirectories