org.jretty.util.resource

类 AbstractResource

java.lang.Object

org.jretty.util.resource.AbstractResource

所有已实现的接口:

InputStreamSource, Resource

直接已知子类:

AbstractFileResolvingResource, ByteArrayResource, DescriptiveResource, FileSystemResource, InputStreamResource, VfsResource

public abstract class AbstractResource
extends Object
implements Resource

Convenience base class for Resource implementations, pre-implementing typical behavior.

The "exists" method will check whether a File or InputStream can be opened; "isOpen" will always return false; "getURL" and "getFile" throw an exception; and "toString" will return the description.

从以下版本开始:

28.12.2003

作者:

Juergen Hoeller

构造器概要

构造器

构造器和说明
AbstractResource()

方法概要

限定符和类型	方法和说明
long	contentLength() This implementation reads the entire InputStream to calculate the content length.
Resource	createRelative(String relativePath) This implementation throws a FileNotFoundException, assuming that relative resources cannot be created for this resource.
boolean	equals(Object obj) This implementation compares description strings.
boolean	exists() This implementation checks whether a File can be opened, falling back to whether an InputStream can be opened.
File	getFile() This implementation throws a FileNotFoundException, assuming that the resource cannot be resolved to an absolute file path.
protected File	getFileForLastModifiedCheck() Determine the File to use for timestamp checking.
String	getFilename() This implementation always returns null, assuming that this resource type does not have a filename.
URI	getURI() This implementation builds a URI based on the URL returned by getURL().
URL	getURL() This implementation throws a FileNotFoundException, assuming that the resource cannot be resolved to a URL.
int	hashCode() This implementation returns the description's hash code.
boolean	isOpen() This implementation always returns false.
boolean	isReadable() This implementation always returns true.
long	lastModified() This implementation checks the timestamp of the underlying File, if available.
String	toString() This implementation returns the description of this resource.

从类继承的方法 java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

从接口继承的方法 org.jretty.util.resource.Resource

getDescription

从接口继承的方法 org.jretty.util.resource.InputStreamSource

getInputStream

构造器详细资料

AbstractResource

public AbstractResource()

方法详细资料

exists

public boolean exists()

This implementation checks whether a File can be opened, falling back to whether an InputStream can be opened. This will cover both directories and content resources.

指定者:

exists 在接口中 Resource

isReadable

public boolean isReadable()

This implementation always returns true.

指定者:

isReadable 在接口中 Resource

另请参阅:

InputStreamSource.getInputStream()

isOpen

public boolean isOpen()

This implementation always returns false.

指定者:

isOpen 在接口中 Resource

getURL

public URL getURL()
           throws IOException

This implementation throws a FileNotFoundException, assuming that the resource cannot be resolved to a URL.

指定者:

getURL 在接口中 Resource

抛出:

IOException - if the resource cannot be resolved as URL, i.e. if the resource is not available as descriptor

getURI

public URI getURI()
           throws IOException

This implementation builds a URI based on the URL returned by getURL().

指定者:

getURI 在接口中 Resource

抛出:

IOException - if the resource cannot be resolved as URI, i.e. if the resource is not available as descriptor

getFile

public File getFile()
             throws IOException

This implementation throws a FileNotFoundException, assuming that the resource cannot be resolved to an absolute file path.

指定者:

getFile 在接口中 Resource

抛出:

IOException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

contentLength

public long contentLength()
                   throws IOException

This implementation reads the entire InputStream to calculate the content length. Subclasses will almost always be able to provide a more optimal version of this, e.g. checking a File length.

指定者:

contentLength 在接口中 Resource

抛出:

IllegalStateException - if InputStreamSource.getInputStream() returns null.

IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

另请参阅:

InputStreamSource.getInputStream()

lastModified

public long lastModified()
                  throws IOException

This implementation checks the timestamp of the underlying File, if available.

指定者:

lastModified 在接口中 Resource

抛出:

IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

另请参阅:

getFileForLastModifiedCheck()

getFileForLastModifiedCheck

protected File getFileForLastModifiedCheck()
                                    throws IOException

Determine the File to use for timestamp checking.

The default implementation delegates to getFile().

返回:

the File to use for timestamp checking (never null)

抛出:

IOException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

createRelative

public Resource createRelative(String relativePath)
                        throws IOException

This implementation throws a FileNotFoundException, assuming that relative resources cannot be created for this resource.

指定者:

createRelative 在接口中 Resource

参数:

relativePath - the relative path (relative to this resource)

返回:

the resource handle for the relative resource

抛出:

IOException - if the relative resource cannot be determined

getFilename

public String getFilename()

This implementation always returns null, assuming that this resource type does not have a filename.

指定者:

getFilename 在接口中 Resource

toString

public String toString()

This implementation returns the description of this resource.

覆盖:

toString 在类中 Object

另请参阅:

Resource.getDescription()

equals

public boolean equals(Object obj)

This implementation compares description strings.

覆盖:

equals 在类中 Object

另请参阅:

Resource.getDescription()

hashCode

public int hashCode()

This implementation returns the description's hash code.

覆盖:

hashCode 在类中 Object

另请参阅:

Resource.getDescription()