NaiveUserAgent (Openhtmltopdf Core Renderer 0.0.1-RC15 API)

java.lang.Object
- com.openhtmltopdf.swing.NaiveUserAgent

All Implemented Interfaces:

DocumentListener, UserAgentCallback

Direct Known Subclasses:

DelegatingUserAgent
```
public class NaiveUserAgent
extends Object
implements UserAgentCallback, DocumentListener
```
NaiveUserAgent is a simple implementation of UserAgentCallback which places no restrictions on what XML, CSS or images are loaded, and reports visited links without any filtering. The most straightforward process available in the JDK is used to load the resources in question--either using java.io or java.net classes.
The NaiveUserAgent has a small cache for images, the size of which (number of images) can be passed as a constructor argument. There is no automatic cleaning of the cache; call #shrinkImageCache() to remove the least-accessed elements--for example, you might do this when a new document is about to be loaded. The NaiveUserAgent is also a DocumentListener; if registered with a source of document events (like the panel hierarchy), it will respond to the DocumentListener.documentStarted() call and attempt to shrink its cache.

Author:

Torbjoern Gannholm

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`NaiveUserAgent.DefaultHttpStream`
`static class`	`NaiveUserAgent.DefaultHttpStreamFactory`
`static class`	`NaiveUserAgent.DefaultUriResolver`
`protected static class`	`NaiveUserAgent.NullCache<T>`
`static class`	`NaiveUserAgent.NullFSCache`

Field Summary

Fields
Modifier and Type	Field and Description
`protected String`	`_baseUri`
`protected FSMultiThreadCache<byte[]>`	`_byteCache`
`protected FSCache`	`_externalCache`
`protected LinkedHashMap<String,ImageResource>`	`_imageCache` a (simple) cache This is only useful for the one run.
`protected Map<String,FSStreamFactory>`	`_protocolsStreamFactory`
`protected FSUriResolver`	`_resolver`
`protected FSMultiThreadCache<String>`	`_textCache`
`protected FSUriResolver`	`DEFAULT_URI_RESOLVER`

Constructor Summary

Constructors
Constructor and Description

NaiveUserAgent()

Constructors
Constructor and Description
`NaiveUserAgent()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clearImageCache()` Empties the image cache entirely.
`void`	`documentLoaded()` Indicates document layout has complete, e.g.
`void`	`documentStarted()` Indicates document has been requested (e.g.
`String`	`getBaseURL()` Returns the current baseUrl for this class.
`byte[]`	`getBinaryResource(String uri)` Retrieves a binary resource located at a given URI and returns its contents as a byte array or `null` if the resource could not be loaded.
`protected Reader`	`getCacheReader(String uri)`
`protected InputStream`	`getCacheStream(String uri)`
`protected String`	`getCacheText(String uri)`
`CSSResource`	`getCSSResource(String uri)` Retrieves the CSS located at the given URI.
`FSUriResolver`	`getDefaultUriResolver()`
`ImageResource`	`getImageResource(String uri)` Retrieves the image located at the given URI.
`protected FSStreamFactory`	`getProtocolFactory(String protocol)`
`XMLResource`	`getXMLResource(String uri)` Retrieves the XML located at the given URI.
`protected boolean`	`hasProtocolFactory(String protocol)`
`boolean`	`isVisited(String uri)` Returns true if the given URI was visited, meaning it was requested at some point since initialization.
`void`	`onLayoutException(Throwable t)` Called when document layout failed with an exception.
`void`	`onRenderException(Throwable t)` Called when document render failed with an exception.
`protected Reader`	`openReader(String uri)` Gets a reader for the identified resource by a resolved URI.
`protected InputStream`	`openStream(String uri)` Gets a InputStream for the resource identified by a resolved URI.
`protected String`	`readAll(Reader reader)`
`String`	`resolveURI(String uri)` Used to find a uri that may be relative to the BaseURL.
`String`	`resolveUri(String baseUri, String uri)`
`void`	`setBaseURL(String uri)` URL relative to which URIs are resolved.
`void`	`setExternalByteCache(FSMultiThreadCache<byte[]> byteCache)`
`void`	`setExternalCache(FSCache cache)`
`void`	`setExternalTextCache(FSMultiThreadCache<String> textCache)`
`void`	`setProtocolsStreamFactory(Map<String,FSStreamFactory> protocolsStreamFactory)`
`void`	`setUriResolver(FSUriResolver resolver)`

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

- Field Detail
  - _imageCache
```
protected final LinkedHashMap<String,ImageResource> _imageCache
```
    a (simple) cache This is only useful for the one run. For more than one run, set an external cache with setFSCache.
  - DEFAULT_URI_RESOLVER
```
protected final FSUriResolver DEFAULT_URI_RESOLVER
```
  - _externalCache
```
protected FSCache _externalCache
```
  - _resolver
```
protected FSUriResolver _resolver
```
  - _baseUri
```
protected String _baseUri
```
  - _protocolsStreamFactory
```
protected Map<String,FSStreamFactory> _protocolsStreamFactory
```
  - _textCache
```
protected FSMultiThreadCache<String> _textCache
```
  - _byteCache
```
protected FSMultiThreadCache<byte[]> _byteCache
```
- Constructor Detail
  - NaiveUserAgent
```
public NaiveUserAgent()
```
- Method Detail
  - setProtocolsStreamFactory
```
public void setProtocolsStreamFactory(Map<String,FSStreamFactory> protocolsStreamFactory)
```
  - setExternalCache
```
public void setExternalCache(FSCache cache)
```
  - setUriResolver
```
public void setUriResolver(FSUriResolver resolver)
```
  - getDefaultUriResolver
```
public FSUriResolver getDefaultUriResolver()
```
  - clearImageCache
```
public void clearImageCache()
```
    Empties the image cache entirely.
  - getProtocolFactory
```
protected FSStreamFactory getProtocolFactory(String protocol)
```
  - hasProtocolFactory
```
protected boolean hasProtocolFactory(String protocol)
```
  - openStream
```
protected InputStream openStream(String uri)
```
    Gets a InputStream for the resource identified by a resolved URI.
  - openReader
```
protected Reader openReader(String uri)
```
    Gets a reader for the identified resource by a resolved URI.
  - getCacheText
```
protected String getCacheText(String uri)
```
  - readAll
```
protected String readAll(Reader reader)
                  throws IOException
```
    Throws:
    
    IOException
  - getCacheReader
```
protected Reader getCacheReader(String uri)
```
  - getCacheStream
```
protected InputStream getCacheStream(String uri)
```
  - getCSSResource
```
public CSSResource getCSSResource(String uri)
```
    Retrieves the CSS located at the given URI. It's assumed the URI does point to a CSS file--the URI will be resolved, accessed (using the set FSStreamFactory or URL::openStream), opened, read and then passed into the CSS parser. The result is packed up into an CSSResource for later consumption.
    
    Specified by:
    
    getCSSResource in interface UserAgentCallback
    
    Parameters:
    
    uri - Location of the CSS source.
    
    Returns:
    
    A CSSResource containing the CSS reader or null if not available.
  - getImageResource
```
public ImageResource getImageResource(String uri)
```
    Retrieves the image located at the given URI. It's assumed the URI does point to an image--the URI will be accessed (using the set HttpStreamFactory or URL::openStream), opened, read and then passed into the JDK image-parsing routines. The result is packed up into an ImageResource for later consumption.
    
    Specified by:
    
    getImageResource in interface UserAgentCallback
    
    Parameters:
    
    uri - Location of the image source.
    
    Returns:
    
    An ImageResource containing the image.
  - getXMLResource
```
public XMLResource getXMLResource(String uri)
```
    Retrieves the XML located at the given URI. It's assumed the URI does point to a XML--the URI will be accessed (using the set HttpStreamFactory or URL::openStream), opened, read and then passed into the XML parser (XMLReader) configured for Flying Saucer. The result is packed up into an XMLResource for later consumption.
    
    Specified by:
    
    getXMLResource in interface UserAgentCallback
    
    Parameters:
    
    uri - Location of the XML source.
    
    Returns:
    
    An XMLResource containing the image.
  - getBinaryResource
```
public byte[] getBinaryResource(String uri)
```
    Description copied from interface: UserAgentCallback
    
    Retrieves a binary resource located at a given URI and returns its contents as a byte array or null if the resource could not be loaded.
    
    Specified by:
    
    getBinaryResource in interface UserAgentCallback
  - isVisited
```
public boolean isVisited(String uri)
```
    Returns true if the given URI was visited, meaning it was requested at some point since initialization.
    
    Specified by:
    
    isVisited in interface UserAgentCallback
    
    Parameters:
    
    uri - A URI which might have been visited.
    
    Returns:
    
    Always false; visits are not tracked in the NaiveUserAgent.
  - setBaseURL
```
public void setBaseURL(String uri)
```
    URL relative to which URIs are resolved.
    
    Specified by:
    
    setBaseURL in interface UserAgentCallback
    
    Parameters:
    
    url - A URI which anchors other, possibly relative URIs.
  - getBaseURL
```
public String getBaseURL()
```
    Returns the current baseUrl for this class.
    
    Specified by:
    
    getBaseURL in interface UserAgentCallback
    
    Returns:
    
    the base uri, possibly in the implementations private uri-space
  - documentStarted
```
public void documentStarted()
```
    Description copied from interface: DocumentListener
    
    Indicates document has been requested (e.g. a new document is going to be loaded). This will be called before any activity takes place for the document.
    
    Specified by:
    
    documentStarted in interface DocumentListener
  - documentLoaded
```
public void documentLoaded()
```
    Description copied from interface: DocumentListener
    
    Indicates document layout has complete, e.g. document is fully "loaded" for display; this is not a callback for the document source (e.g. XML) being loaded. This method will be called on every layout run (including, for example, after panel resizes).
    
    Specified by:
    
    documentLoaded in interface DocumentListener
  - onLayoutException
```
public void onLayoutException(Throwable t)
```
    Description copied from interface: DocumentListener
    
    Called when document layout failed with an exception. All Throwable objects thrown (except for ThreadDeath) during layout and not otherwise handled will be provided to this method. If a DocumentListener has been defined an XHTML panel, the listener is entirely responsible for handling the exception. No other action will be taken.
    
    Specified by:
    
    onLayoutException in interface DocumentListener
  - onRenderException
```
public void onRenderException(Throwable t)
```
    Description copied from interface: DocumentListener
    
    Called when document render failed with an exception. All Throwable objects thrown (except for ThreadDeath) during render and not otherwise handled will be provided to this method. If a DocumentListener has been defined an XHTML panel, the listener is entirely responsible for handling the exception. No other action will be taken.
    
    Specified by:
    
    onRenderException in interface DocumentListener
  - resolveURI
```
public String resolveURI(String uri)
```
    Description copied from interface: UserAgentCallback
    
    Used to find a uri that may be relative to the BaseURL. The returned value will always only be used via methods in the same implementation of this interface, therefore may be a private uri-space.
    
    Specified by:
    
    resolveURI in interface UserAgentCallback
    
    Parameters:
    
    uri - an absolute or relative (to baseURL) uri to be resolved.
    
    Returns:
    
    the full uri in uri-spaces known to the current implementation.
  - resolveUri
```
public String resolveUri(String baseUri,
                         String uri)
```
    Specified by:
    
    resolveUri in interface UserAgentCallback
  - setExternalTextCache
```
public void setExternalTextCache(FSMultiThreadCache<String> textCache)
```
  - setExternalByteCache
```
public void setExternalByteCache(FSMultiThreadCache<byte[]> byteCache)
```

Class NaiveUserAgent

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

_imageCache

DEFAULT_URI_RESOLVER

_externalCache

_resolver

_baseUri

_protocolsStreamFactory

_textCache

_byteCache

Constructor Detail

NaiveUserAgent

Method Detail

setProtocolsStreamFactory

setExternalCache

setUriResolver

getDefaultUriResolver

clearImageCache

getProtocolFactory

hasProtocolFactory

openStream

openReader

getCacheText

readAll

getCacheReader

getCacheStream

getCSSResource

getImageResource

getXMLResource

getBinaryResource

isVisited

setBaseURL

getBaseURL

documentStarted

documentLoaded

onLayoutException

onRenderException

resolveURI

resolveUri

setExternalTextCache

setExternalByteCache