org.apache.camel.util

Class ResourceHelper

java.lang.Object

org.apache.camel.util.ResourceHelper

public final class ResourceHelper
extends Object

Helper class for loading resources on the classpath or file system.

Method Summary

Modifier and Type	Method and Description
static String	appendParameters(String uri, Map<String,Object> parameters) Appends the parameters to the given uri
static String	getScheme(String uri) Gets the scheme from the URI (e.g.
static boolean	hasScheme(String uri) Determines whether the URI has a scheme (e.g.
static boolean	isHttpUri(String uri) Is the given uri a http uri?
static InputStream	resolveMandatoryResourceAsInputStream(CamelContext camelContext, String uri) Resolves the mandatory resource.
static InputStream	resolveMandatoryResourceAsInputStream(ClassResolver classResolver, String uri) Deprecated. use resolveMandatoryResourceAsInputStream(CamelContext, String)
static URL	resolveMandatoryResourceAsUrl(ClassResolver classResolver, String uri) Resolves the mandatory resource.
static String	resolveOptionalExternalScript(CamelContext camelContext, Exchange exchange, String expression) Resolves the expression/predicate whether it refers to an external script on the file/classpath etc.
static String	resolveOptionalExternalScript(CamelContext camelContext, String expression) Resolves the expression/predicate whether it refers to an external script on the file/classpath etc.
static InputStream	resolveResourceAsInputStream(ClassResolver classResolver, String uri) Resolves the resource.
static URL	resolveResourceAsUrl(ClassResolver classResolver, String uri) Resolves the resource.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

resolveOptionalExternalScript

public static String resolveOptionalExternalScript(CamelContext camelContext,
                                                   String expression)

Resolves the expression/predicate whether it refers to an external script on the file/classpath etc. This requires to use the prefix resource: such as resource:classpath:com/foo/myscript.groovy, resource:file:/var/myscript.groovy.

If not then the returned value is returned as-is.

resolveOptionalExternalScript

public static String resolveOptionalExternalScript(CamelContext camelContext,
                                                   Exchange exchange,
                                                   String expression)

Resolves the expression/predicate whether it refers to an external script on the file/classpath etc. This requires to use the prefix resource: such as resource:classpath:com/foo/myscript.groovy, resource:file:/var/myscript.groovy.

If not then the returned value is returned as-is.

If the exchange is provided (not null), then the external script can be referred via simple language for dynamic values, etc. resource:classpath:${header.myFileName}

hasScheme

public static boolean hasScheme(String uri)

Determines whether the URI has a scheme (e.g. file:, classpath: or http:)

Parameters:

uri - the URI

Returns:

true if the URI starts with a scheme

getScheme

public static String getScheme(String uri)

Gets the scheme from the URI (e.g. file:, classpath: or http:)

Parameters:

uri - the uri

Returns:

the scheme, or null if no scheme

resolveMandatoryResourceAsInputStream

public static InputStream resolveMandatoryResourceAsInputStream(CamelContext camelContext,
                                                                String uri)
                                                         throws IOException

Resolves the mandatory resource.

The resource uri can refer to the following systems to be loaded from

file:nameOfFile - to refer to the file system classpath:nameOfFile - to refer to the classpath (default) http:uri - to load the resource using HTTP ref:nameOfBean - to lookup the resource in the Registry bean:nameOfBean.methodName or bean:nameOfBean::methodName - to lookup a bean in the Registry and call the method :uri - to lookup the resource using a custom URLStreamHandler registered for the , on how to register it @see java.net.URL#URL(java.lang.String, java.lang.String, int, java.lang.String)

If no prefix has been given, then the resource is loaded from the classpath

If possible recommended to use resolveMandatoryResourceAsUrl(org.apache.camel.spi.ClassResolver, String)

Parameters:

camelContext - the Camel Context

uri - URI of the resource

Returns:

the resource as an InputStream. Remember to close this stream after usage.

Throws:

IOException - is thrown if the resource file could not be found or loaded as InputStream

resolveMandatoryResourceAsInputStream

@Deprecated
public static InputStream resolveMandatoryResourceAsInputStream(ClassResolver classResolver,
                                                                            String uri)
                                                                     throws IOException

Deprecated. use resolveMandatoryResourceAsInputStream(CamelContext, String)

Resolves the mandatory resource.

If possible recommended to use resolveMandatoryResourceAsUrl(org.apache.camel.spi.ClassResolver, String)

Parameters:

classResolver - the class resolver to load the resource from the classpath

uri - URI of the resource

Returns:

the resource as an InputStream. Remember to close this stream after usage.

Throws:

IOException - is thrown if the resource file could not be found or loaded as InputStream

resolveResourceAsInputStream

public static InputStream resolveResourceAsInputStream(ClassResolver classResolver,
                                                       String uri)
                                                throws IOException

Resolves the resource.

If possible recommended to use resolveMandatoryResourceAsUrl(org.apache.camel.spi.ClassResolver, String)

Parameters:

classResolver - the class resolver to load the resource from the classpath

uri - URI of the resource

Returns:

the resource as an InputStream. Remember to close this stream after usage. Or null if not found.

Throws:

IOException - is thrown if error loading the resource

resolveMandatoryResourceAsUrl

public static URL resolveMandatoryResourceAsUrl(ClassResolver classResolver,
                                                String uri)
                                         throws FileNotFoundException,
                                                MalformedURLException

Resolves the mandatory resource.

Parameters:

classResolver - the class resolver to load the resource from the classpath

uri - uri of the resource

Returns:

the resource as an URL.

Throws:

FileNotFoundException - is thrown if the resource file could not be found

MalformedURLException - if the URI is malformed

resolveResourceAsUrl

public static URL resolveResourceAsUrl(ClassResolver classResolver,
                                       String uri)
                                throws MalformedURLException

Resolves the resource.

Parameters:

classResolver - the class resolver to load the resource from the classpath

uri - uri of the resource

Returns:

the resource as an URL. Or null if not found.

Throws:

MalformedURLException - if the URI is malformed

isHttpUri

public static boolean isHttpUri(String uri)

Is the given uri a http uri?

Parameters:

uri - the uri

Returns:

true if the uri starts with http: or https:

appendParameters

public static String appendParameters(String uri,
                                      Map<String,Object> parameters)
                               throws URISyntaxException

Appends the parameters to the given uri

Parameters:

uri - the uri

parameters - the additional parameters (will clear the map)

Returns:

a new uri with the additional parameters appended

Throws:

URISyntaxException - is thrown if the uri is invalid