java.lang.Object
- spark.utils.ResourceUtils

```
public abstract class ResourceUtils
extends java.lang.Object
```
Utility methods for resolving resource locations to files in the file system. Mainly for internal use within the framework.
Consider using Spring's Resource abstraction in the core package for handling all kinds of file resources in a uniform manner. org.springframework.core.io.ResourceLoader @code getResource() method can resolve any location to a org.springframework.core.io.Resource object, which in turn allows one to obtain a java.io.File in the file system through its getFile() method.
The main reason for these utility methods for resource location handling is to support Log4jConfigurer, which must be able to resolve resource locations before the logging system has been initialized. Spring's Resource abstraction in the core package, on the other hand, already expects the logging system to be available.

Since:

1.1.5 Code copied from Spring source. Modifications made (mostly removal of methods) by Per Wendel.

Field Summary

Fields
Modifier and Type	Field	Description
`static java.lang.String`	`CLASSPATH_URL_PREFIX`	Pseudo URL prefix for loading from the class path: "classpath:"
`static java.lang.String`	`FILE_URL_PREFIX`	URL prefix for loading from the file system: "file:"
`static java.lang.String`	`JAR_URL_SEPARATOR`	Separator between JAR URL and file path within the JAR
`static java.lang.String`	`URL_PROTOCOL_FILE`	URL protocol for a file in the file system: "file"
`static java.lang.String`	`URL_PROTOCOL_JAR`	URL protocol for an entry from a jar file: "jar"
`static java.lang.String`	`URL_PROTOCOL_VFSZIP`	URL protocol for an entry from a JBoss jar file: "vfszip"
`static java.lang.String`	`URL_PROTOCOL_WSJAR`	URL protocol for an entry from a WebSphere jar file: "wsjar"
`static java.lang.String`	`URL_PROTOCOL_ZIP`	URL protocol for an entry from a zip file: "zip"

Constructor Summary

Constructors
Constructor Description

ResourceUtils()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static java.net.URL`	`extractJarFileURL(java.net.URL jarUrl)`	Extract the URL for the actual jar file from the given URL (which may point to a resource in a jar file or to a jar file itself).
`static java.io.File`	`getFile(java.lang.String resourceLocation)`	Resolve the given resource location to a `java.io.File`, i.e.
`static java.io.File`	`getFile(java.net.URI resourceUri)`	Resolve the given resource URI to a `java.io.File`, i.e.
`static java.io.File`	`getFile(java.net.URI resourceUri, java.lang.String description)`	Resolve the given resource URI to a `java.io.File`, i.e.
`static java.io.File`	`getFile(java.net.URL resourceUrl)`	Resolve the given resource URL to a `java.io.File`, i.e.
`static java.io.File`	`getFile(java.net.URL resourceUrl, java.lang.String description)`	Resolve the given resource URL to a `java.io.File`, i.e.
`static java.net.URL`	`getURL(java.lang.String resourceLocation)`	Resolve the given resource location to a `java.net.URL`.
`static boolean`	`isFileURL(java.net.URL url)`	Determine whether the given URL points to a resource in the file system, that is, has protocol "file" or "vfs".
`static boolean`	`isJarURL(java.net.URL url)`	Determine whether the given URL points to a resource in a jar file, that is, has protocol "jar", "zip", "wsjar" or "code-source".
`static boolean`	`isUrl(java.lang.String resourceLocation)`	Return whether the given resource location is a URL: either a special "classpath" pseudo URL or a standard URL.
`static java.net.URI`	`toURI(java.lang.String location)`	Create a URI instance for the given location String, replacing spaces with "%20" URI encoding first.
`static java.net.URI`	`toURI(java.net.URL url)`	Create a URI instance for the given URL, replacing spaces with "%20" URI encoding first.
`static void`	`useCachesIfNecessary(java.net.URLConnection con)`	Set the `"useCaches"` flag on the given connection, preferring `false` but leaving the flag at `true` for JNLP based resources.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - CLASSPATH_URL_PREFIX
```
public static final java.lang.String CLASSPATH_URL_PREFIX
```
    Pseudo URL prefix for loading from the class path: "classpath:"
    
    See Also:
    
    Constant Field Values
  - FILE_URL_PREFIX
```
public static final java.lang.String FILE_URL_PREFIX
```
    URL prefix for loading from the file system: "file:"
    
    See Also:
    
    Constant Field Values
  - URL_PROTOCOL_FILE
```
public static final java.lang.String URL_PROTOCOL_FILE
```
    URL protocol for a file in the file system: "file"
    
    See Also:
    
    Constant Field Values
  - URL_PROTOCOL_JAR
```
public static final java.lang.String URL_PROTOCOL_JAR
```
    URL protocol for an entry from a jar file: "jar"
    
    See Also:
    
    Constant Field Values
  - URL_PROTOCOL_ZIP
```
public static final java.lang.String URL_PROTOCOL_ZIP
```
    URL protocol for an entry from a zip file: "zip"
    
    See Also:
    
    Constant Field Values
  - URL_PROTOCOL_VFSZIP
```
public static final java.lang.String URL_PROTOCOL_VFSZIP
```
    URL protocol for an entry from a JBoss jar file: "vfszip"
    
    See Also:
    
    Constant Field Values
  - URL_PROTOCOL_WSJAR
```
public static final java.lang.String URL_PROTOCOL_WSJAR
```
    URL protocol for an entry from a WebSphere jar file: "wsjar"
    
    See Also:
    
    Constant Field Values
  - JAR_URL_SEPARATOR
```
public static final java.lang.String JAR_URL_SEPARATOR
```
    Separator between JAR URL and file path within the JAR
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - ResourceUtils
```
public ResourceUtils()
```
- Method Detail
  - isUrl
```
public static boolean isUrl(java.lang.String resourceLocation)
```
    Return whether the given resource location is a URL: either a special "classpath" pseudo URL or a standard URL.
    
    Parameters:
    
    resourceLocation - the location String to check
    
    Returns:
    
    whether the location qualifies as a URL
    
    See Also:
    
    CLASSPATH_URL_PREFIX, URL
  - getURL
```
public static java.net.URL getURL(java.lang.String resourceLocation)
                           throws java.io.FileNotFoundException
```
    Resolve the given resource location to a java.net.URL.
    Does not check whether the URL actually exists; simply returns the URL that the given location would correspond to.
    
    Parameters:
    
    resourceLocation - the resource location to resolve: either a "classpath:" pseudo URL, a "file:" URL, or a plain file path
    
    Returns:
    
    a corresponding URL object
    
    Throws:
    
    java.io.FileNotFoundException - if the resource cannot be resolved to a URL
  - getFile
```
public static java.io.File getFile(java.lang.String resourceLocation)
                            throws java.io.FileNotFoundException
```
    Resolve the given resource location to a java.io.File, i.e. to a file in the file system.
    Does not check whether the file actually exists; simply returns the File that the given location would correspond to.
    
    Parameters:
    
    resourceLocation - the resource location to resolve: either a "classpath:" pseudo URL, a "file:" URL, or a plain file path
    
    Returns:
    
    a corresponding File object
    
    Throws:
    
    java.io.FileNotFoundException - if the resource cannot be resolved to a file in the file system
  - getFile
```
public static java.io.File getFile(java.net.URL resourceUrl)
                            throws java.io.FileNotFoundException
```
    Resolve the given resource URL to a java.io.File, i.e. to a file in the file system.
    
    Parameters:
    
    resourceUrl - the resource URL to resolve
    
    Returns:
    
    a corresponding File object
    
    Throws:
    
    java.io.FileNotFoundException - if the URL cannot be resolved to a file in the file system
  - getFile
```
public static java.io.File getFile(java.net.URL resourceUrl,
                                   java.lang.String description)
                            throws java.io.FileNotFoundException
```
    Resolve the given resource URL to a java.io.File, i.e. to a file in the file system.
    
    Parameters:
    
    resourceUrl - the resource URL to resolve
    
    description - a description of the original resource that the URL was created for (for example, a class path location)
    
    Returns:
    
    a corresponding File object
    
    Throws:
    
    java.io.FileNotFoundException - if the URL cannot be resolved to a file in the file system
  - getFile
```
public static java.io.File getFile(java.net.URI resourceUri)
                            throws java.io.FileNotFoundException
```
    Resolve the given resource URI to a java.io.File, i.e. to a file in the file system.
    
    Parameters:
    
    resourceUri - the resource URI to resolve
    
    Returns:
    
    a corresponding File object
    
    Throws:
    
    java.io.FileNotFoundException - if the URL cannot be resolved to a file in the file system
  - getFile
```
public static java.io.File getFile(java.net.URI resourceUri,
                                   java.lang.String description)
                            throws java.io.FileNotFoundException
```
    Resolve the given resource URI to a java.io.File, i.e. to a file in the file system.
    
    Parameters:
    
    resourceUri - the resource URI to resolve
    
    description - a description of the original resource that the URI was created for (for example, a class path location)
    
    Returns:
    
    a corresponding File object
    
    Throws:
    
    java.io.FileNotFoundException - if the URL cannot be resolved to a file in the file system
  - isFileURL
```
public static boolean isFileURL(java.net.URL url)
```
    Determine whether the given URL points to a resource in the file system, that is, has protocol "file" or "vfs".
    
    Parameters:
    
    url - the URL to check
    
    Returns:
    
    whether the URL has been identified as a file system URL
  - isJarURL
```
public static boolean isJarURL(java.net.URL url)
```
    Determine whether the given URL points to a resource in a jar file, that is, has protocol "jar", "zip", "wsjar" or "code-source".
    "zip" and "wsjar" are used by WebLogic Server and WebSphere, respectively, but can be treated like jar files.
    
    Parameters:
    
    url - the URL to check
    
    Returns:
    
    whether the URL has been identified as a JAR URL
  - extractJarFileURL
```
public static java.net.URL extractJarFileURL(java.net.URL jarUrl)
                                      throws java.net.MalformedURLException
```
    Extract the URL for the actual jar file from the given URL (which may point to a resource in a jar file or to a jar file itself).
    
    Parameters:
    
    jarUrl - the original URL
    
    Returns:
    
    the URL for the actual jar file
    
    Throws:
    
    java.net.MalformedURLException - if no valid jar file URL could be extracted
  - toURI
```
public static java.net.URI toURI(java.net.URL url)
                          throws java.net.URISyntaxException
```
    Create a URI instance for the given URL, replacing spaces with "%20" URI encoding first.
    Furthermore, this method works on JDK 1.4 as well, in contrast to the URL.toURI() method.
    
    Parameters:
    
    url - the URL to convert into a URI instance
    
    Returns:
    
    the URI instance
    
    Throws:
    
    java.net.URISyntaxException - if the URL wasn't a valid URI
    
    See Also:
    
    URL.toURI()
  - toURI
```
public static java.net.URI toURI(java.lang.String location)
                          throws java.net.URISyntaxException
```
    Create a URI instance for the given location String, replacing spaces with "%20" URI encoding first.
    
    Parameters:
    
    location - the location String to convert into a URI instance
    
    Returns:
    
    the URI instance
    
    Throws:
    
    java.net.URISyntaxException - if the location wasn't a valid URI
  - useCachesIfNecessary
```
public static void useCachesIfNecessary(java.net.URLConnection con)
```
    Set the "useCaches" flag on the given connection, preferring false but leaving the flag at true for JNLP based resources.
    
    Parameters:
    
    con - the URLConnection to set the flag on

Class ResourceUtils

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

CLASSPATH_URL_PREFIX

FILE_URL_PREFIX

URL_PROTOCOL_FILE

URL_PROTOCOL_JAR

URL_PROTOCOL_ZIP

URL_PROTOCOL_VFSZIP

URL_PROTOCOL_WSJAR

JAR_URL_SEPARATOR

Constructor Detail

ResourceUtils

Method Detail

isUrl

getURL

getFile

getFile

getFile

getFile

getFile

isFileURL

isJarURL

extractJarFileURL

toURI

toURI

useCachesIfNecessary