package com.bigdata.bfs;
import java.io.InputStream;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import com.bigdata.sparse.IRowStoreConstants;
import com.bigdata.sparse.ITPS;
import com.bigdata.sparse.ITPV;
/**
* A read-only view of a {@link Document} that has been read from a
* {@link BigdataFileSystem}.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public class RepositoryDocumentImpl implements DocumentHeader, Document
{
final private BigdataFileSystem repo;
final private String id;
/**
* The result of the atomic read on the file's metadata. This
* representation is significantly richer than the current set of
* property values.
*/
final ITPS tps;
/**
* The current version identifer -or- <code>-1</code> iff there is no
* current version for the file (including when there is no record of
* any version for the file).
*/
final int version;
/**
* The property set for the current file version.
*/
final private Map<String,Object> metadata;
/**
* Read the metadata for the current version of the file from the
* repository.
*
* @param id
* The file identifier.
* @param tps
* The logical row describing the metadata for some file in
* the repository.
*/
public RepositoryDocumentImpl(final BigdataFileSystem repo, final String id,
final ITPS tps) {
if (repo == null)
throw new IllegalArgumentException();
if (id == null)
throw new IllegalArgumentException();
this.repo = repo;
this.id = id;
this.tps = tps;
if (tps != null) {
ITPV tmp = tps.get(FileMetadataSchema.VERSION);
if (tmp.getValue() != null) {
/*
* Note the current version identifer.
*/
this.version = (Integer) tmp.getValue();
/*
* Save a simplifed view of the propery set for the current
* version.
*/
this.metadata = tps.asMap();
BigdataFileSystem.log.info("id="+id+", current version="+version);
} else {
/*
* No current version.
*/
this.version = -1;
this.metadata = null;
BigdataFileSystem.log.warn("id="+id+" : no current version");
}
} else {
/*
* Nothing on record for that file identifier.
*/
this.version = -1;
this.metadata = null;
BigdataFileSystem.log.warn("id="+id+" : no record of any version(s)");
}
if (BigdataFileSystem.DEBUG && metadata != null) {
Iterator<Map.Entry<String,Object>> itr = metadata.entrySet().iterator();
while(itr.hasNext()) {
Map.Entry<String, Object> entry = itr.next();
BigdataFileSystem.log.debug("id=" + id + ", version=" + getVersion() + ", ["
+ entry.getKey() + "]=[" + entry.getValue() + "]");
}
}
}
/**
* Read the metadata for the current version of the file from the
* repository.
*
* @param id
* The file identifier.
*/
public RepositoryDocumentImpl(final BigdataFileSystem repo, final String id) {
this(repo, id, repo.getFileMetadataIndex().read(
BigdataFileSystem.metadataSchema, id,
IRowStoreConstants.MIN_TIMESTAMP,
IRowStoreConstants.CURRENT_ROW, null/* filter */));
}
/**
* Assert that a version of the file existed when this view was constructed.
*
* @throws IllegalStateException
* unless a version of the file existed at the time that this
* view was constructed.
*/
final protected void assertExists() {
if (version == -1) {
throw new IllegalStateException("No current version: id="+id);
}
}
final public boolean exists() {
return version != -1;
}
final public int getVersion() {
assertExists();
return (Integer)metadata.get(FileMetadataSchema.VERSION);
}
/**
* Note: This is obtained from the earliest available timestamp of the
* {@link FileMetadataSchema#ID} property.
*/
final public long getEarliestVersionCreateTime() {
assertExists();
Iterator<ITPV> itr = tps.iterator();
while(itr.hasNext()) {
ITPV tpv = itr.next();
if(tpv.getName().equals(FileMetadataSchema.ID)) {
return tpv.getTimestamp();
}
}
throw new AssertionError();
}
final public long getVersionCreateTime() {
assertExists();
/*
* The timestamp for the most recent value of the VERSION property.
*/
final long createTime = tps.get(FileMetadataSchema.VERSION)
.getTimestamp();
return createTime;
}
final public long getMetadataUpdateTime() {
assertExists();
/*
* The timestamp for the most recent value of the ID property.
*/
final long metadataUpdateTime = tps.get(FileMetadataSchema.ID)
.getTimestamp();
return metadataUpdateTime;
}
/**
* Return an array containing all non-eradicated values of the
* {@link FileMetadataSchema#VERSION} property for this file as of the time
* that this view was constructed.
*
* @see BigdataFileSystem#getAllVersionInfo(String)
*/
final public ITPV[] getAllVersionInfo() {
return repo.getAllVersionInfo(id);
}
final public InputStream getInputStream() {
assertExists();
return repo.inputStream(id,getVersion());
}
final public Reader getReader() throws UnsupportedEncodingException {
assertExists();
return repo.reader(id, getVersion(), getContentEncoding());
}
final public String getContentEncoding() {
assertExists();
return (String)metadata.get(FileMetadataSchema.CONTENT_ENCODING);
}
final public String getContentType() {
assertExists();
return (String)metadata.get(FileMetadataSchema.CONTENT_TYPE);
}
final public String getId() {
return id;
}
final public Object getProperty(String name) {
return metadata.get(name);
}
final public Map<String,Object> asMap() {
assertExists();
return Collections.unmodifiableMap( metadata );
}
}