X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Forg%2Fibex%2Fjs%2FStream.java;fp=src%2Forg%2Fibex%2Fjs%2FStream.java;h=878afa33dc04b595482fa87b41e66cf8affa6f39;hb=4daeeb4119b901d53b44913c86f8af3ce67db925;hp=0000000000000000000000000000000000000000;hpb=da1f843588c8bd2b2c7cc74a5b4ffff8d57ab712;p=org.ibex.core.git diff --git a/src/org/ibex/js/Stream.java b/src/org/ibex/js/Stream.java new file mode 100644 index 0000000..878afa3 --- /dev/null +++ b/src/org/ibex/js/Stream.java @@ -0,0 +1,157 @@ +// Copyright 2004 Adam Megacz, see the COPYING file for licensing [GPL] +package org.ibex; + +import java.io.*; +import java.util.zip.*; +import org.ibex.js.*; +import org.ibex.util.*; +import org.ibex.translators.MSPack; + +/** + * Essentiall an InputStream "factory". You can repeatedly ask a + * Stream for an InputStream, and each InputStream you get back will + * be totally independent of the others (ie separate stream position + * and state) although they draw from the same data source. + */ +public abstract class Stream extends JS.Cloneable { + + // Public Interface ////////////////////////////////////////////////////////////////////////////// + + public static InputStream getInputStream(Object js) throws IOException { return ((Stream)((JS)js).unclone()).getInputStream();} + public static class NotCacheableException extends Exception { } + + // streams are "sealed" by default to prevent accidental object leakage + public void put(Object key, Object val) { } + private Cache getCache = new Cache(100); + protected Object _get(Object key) { return null; } + public final Object get(Object key) { + Object ret = getCache.get(key); + if (ret == null) getCache.put(key, ret = _get(key)); + return ret; + } + + // Private Interface ////////////////////////////////////////////////////////////////////////////// + + protected abstract InputStream getInputStream() throws IOException; + protected String getCacheKey() throws NotCacheableException { throw new NotCacheableException(); } + + /** HTTP or HTTPS resource */ + public static class HTTP extends Stream { + private String url; + public String toString() { return "Stream.HTTP:" + url; } + HTTP(String url) { while (url.endsWith("/")) url = url.substring(0, url.length() - 1); this.url = url; } + public Object _get(Object key) { return new HTTP(url + "/" + (String)key); } + public String getCacheKey(Vec path) throws NotCacheableException { return url; } + public InputStream getInputStream() throws IOException { return new org.ibex.HTTP(url).GET(); } + } + + /** byte arrays */ + public static class ByteArray extends Stream { + private byte[] bytes; + private String cacheKey; + ByteArray(byte[] bytes, String cacheKey) { this.bytes = bytes; this.cacheKey = cacheKey; } + public String getCacheKey() throws NotCacheableException { + if (cacheKey == null) throw new NotCacheableException(); return cacheKey; } + public InputStream getInputStream() throws IOException { return new ByteArrayInputStream(bytes); } + } + + /** a file */ + public static class File extends Stream { + private String path; + File(String path) { this.path = path; } + public String toString() { return "file:" + path; } + public String getCacheKey() throws NotCacheableException { throw new NotCacheableException(); /* already on disk */ } + public InputStream getInputStream() throws IOException { return new FileInputStream(path); } + public Object _get(Object key) { return new File(path + java.io.File.separatorChar + (String)key); } + } + + /** "unwrap" a Zip archive */ + public static class Zip extends Stream { + private Stream parent; + private String path; + Zip(Stream parent) { this(parent, null); } + Zip(Stream parent, String path) { + while(path != null && path.startsWith("/")) path = path.substring(1); + this.parent = parent; + this.path = path; + } + public String getCacheKey() throws NotCacheableException { return parent.getCacheKey() + "!zip:"; } + public Object _get(Object key) { return new Zip(parent, path==null?(String)key:path+'/'+(String)key); } + public InputStream getInputStream() throws IOException { + InputStream pis = parent.getInputStream(); + ZipInputStream zis = new ZipInputStream(pis); + ZipEntry ze = zis.getNextEntry(); + while(ze != null && !ze.getName().equals(path)) ze = zis.getNextEntry(); + if (ze == null) throw new IOException("requested file (" + path + ") not found in archive"); + return new KnownLength.KnownLengthInputStream(zis, (int)ze.getSize()); + } + } + + /** "unwrap" a Cab archive */ + public static class Cab extends Stream { + private Stream parent; + private String path; + Cab(Stream parent) { this(parent, null); } + Cab(Stream parent, String path) { this.parent = parent; this.path = path; } + public String getCacheKey() throws NotCacheableException { return parent.getCacheKey() + "!cab:"; } + public Object _get(Object key) { return new Cab(parent, path==null?(String)key:path+'/'+(String)key); } + public InputStream getInputStream() throws IOException { return new MSPack(parent.getInputStream()).getInputStream(path); } + } + + /** the Builtin resource */ + public static class Builtin extends Stream { + public String getCacheKey() throws NotCacheableException { throw new NotCacheableException(); } + public InputStream getInputStream() throws IOException { return Platform.getBuiltinInputStream(); } + } + + /** shadow resource which replaces the graft */ + public static class ProgressWatcher extends Stream { + final Stream watchee; + JS callback; + ProgressWatcher(Stream watchee, JS callback) { this.watchee = watchee; this.callback = callback; } + public String getCacheKey() throws NotCacheableException { return watchee.getCacheKey(); } + public InputStream getInputStream() throws IOException { + final InputStream is = watchee.getInputStream(); + return new FilterInputStream(is) { + int bytesDownloaded = 0; + public int read() throws IOException { + int ret = super.read(); + if (ret != -1) bytesDownloaded++; + return ret; + } + public int read(byte[] b, int off, int len) throws IOException { + int ret = super.read(b, off, len); + if (ret != 1) bytesDownloaded += ret; + Scheduler.add(new Scheduler.Task() { public void perform() throws IOException, JSExn { + callback.call(N(bytesDownloaded), + N(is instanceof KnownLength ? ((KnownLength)is).getLength() : 0), null, null, 2); + } }); + return ret; + } + }; + } + } + + /** subclass from this if you want a CachedInputStream for each path */ + public static class CachedStream extends Stream { + private Stream parent; + private boolean disk = false; + private String key; + public String getCacheKey() throws NotCacheableException { return key; } + CachedInputStream cis = null; + public CachedStream(Stream p, String s, boolean d) throws NotCacheableException { + this.parent = p; this.disk = d; this.key = p.getCacheKey(); + } + public InputStream getInputStream() throws IOException { + if (cis != null) return cis.getInputStream(); + if (!disk) { + cis = new CachedInputStream(parent.getInputStream()); + } else { + java.io.File f = LocalStorage.Cache.getCacheFileForKey(key); + if (f.exists()) return new FileInputStream(f); + cis = new CachedInputStream(parent.getInputStream(), f); + } + return cis.getInputStream(); + } + } +}