com.google.gwt.dev.util

Class DiskCache

java.lang.Object

com.google.gwt.dev.util.DiskCache

public class DiskCache
extends Object

A nifty class that lets you squirrel away data on the file system. Write once, read many times. Instance of this are thread-safe by way of internal synchronization. Note that in the current implementation, the backing temp file will get arbitrarily large as you continue adding things to it. There is no internal GC or compaction.

Field Summary

Fields

Modifier and Type	Field and Description
static DiskCache	INSTANCE A global shared Disk cache.

Method Summary

Modifier and Type	Method and Description
protected void	finalize() Never called; here for JRE compatibility.
byte[]	readByteArray(long token) Retrieve the underlying bytes.
<T> T	readObject(long token, Class<T> type) Deserialize the underlying bytes as an object.
String	readString(long token) Read the underlying bytes as a String.
long	transferFromStream(InputStream in) Write the rest of the data in an input stream to disk.
void	transferToStream(long token, OutputStream out) Writes the underlying bytes into the specified output stream.
long	writeByteArray(byte[] bytes) Write a byte array to disk.
long	writeObject(Object object) Serialize an Object to disk.
long	writeString(String str) Write a String to disk as bytes.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, toString

Field Detail

INSTANCE

public static DiskCache INSTANCE

A global shared Disk cache.

Method Detail

readByteArray

public byte[] readByteArray(long token)

Retrieve the underlying bytes.

Parameters:

token - a previously returned token

Returns:

the bytes that were written

readObject

public <T> T readObject(long token,
                        Class<T> type)

Deserialize the underlying bytes as an object.

Type Parameters:

T - the type of the object to deserialize

Parameters:

token - a previously returned token

type - the type of the object to deserialize

Returns:

the deserialized object

readString

public String readString(long token)

Read the underlying bytes as a String.

Parameters:

token - a previously returned token

Returns:

the String that was written

transferFromStream

public long transferFromStream(InputStream in)
                        throws IOException

Write the rest of the data in an input stream to disk. Note: this method does not close the InputStream.

Parameters:

in - open stream containing the data to write to the disk cache.

Returns:

a token to retrieve the data later

Throws:

IOException

transferToStream

public void transferToStream(long token,
                             OutputStream out)
                      throws IOException

Writes the underlying bytes into the specified output stream.

Parameters:

token - a previously returned token

out - the stream to write into

Throws:

IOException

writeByteArray

public long writeByteArray(byte[] bytes)

Write a byte array to disk.

Returns:

a token to retrieve the data later

writeObject

public long writeObject(Object object)

Serialize an Object to disk.

Returns:

a token to retrieve the data later

writeString

public long writeString(String str)

Write a String to disk as bytes.

Returns:

a token to retrieve the data later

finalize

protected void finalize()
                 throws Throwable

Description copied from class: Object

Never called; here for JRE compatibility.

Overrides:

finalize in class Object

Throws:

Throwable