@ -94,40 +94,42 @@ public class HeapModifier extends HeapReader implements BLOB {
* @param key the primary key
* @throws IOException
* /
public synchronized void remove ( byte [ ] key ) throws IOException {
public void remove ( byte [ ] key ) throws IOException {
key = normalizeKey ( key ) ;
// check if the index contains the key
final long seek = index . get ( key ) ;
if ( seek < 0 ) return ;
// check consistency of the index
assert ( checkKey ( key , seek ) ) : "key compare failed; key = " + new String ( key ) + ", seek = " + seek ;
// access the file and read the container
this . file . seek ( seek ) ;
int size = file . readInt ( ) ;
//assert seek + size + 4 <= this.file.length() : heapFile.getName() + ": too long size " + size + " in record at " + seek;
long filelength = this . file . length ( ) ; // put in separate variable for debugging
if ( seek + size + 4 > filelength ) {
Log . logSevere ( "BLOBHeap" , heapFile . getName ( ) + ": too long size " + size + " in record at " + seek ) ;
throw new IOException ( heapFile . getName ( ) + ": too long size " + size + " in record at " + seek ) ;
synchronized ( this ) {
// check if the index contains the key
final long seek = index . get ( key ) ;
if ( seek < 0 ) return ;
// check consistency of the index
assert ( checkKey ( key , seek ) ) : "key compare failed; key = " + new String ( key ) + ", seek = " + seek ;
// access the file and read the container
this . file . seek ( seek ) ;
int size = file . readInt ( ) ;
//assert seek + size + 4 <= this.file.length() : heapFile.getName() + ": too long size " + size + " in record at " + seek;
long filelength = this . file . length ( ) ; // put in separate variable for debugging
if ( seek + size + 4 > filelength ) {
Log . logSevere ( "BLOBHeap" , heapFile . getName ( ) + ": too long size " + size + " in record at " + seek ) ;
throw new IOException ( heapFile . getName ( ) + ": too long size " + size + " in record at " + seek ) ;
}
// add entry to free array
this . free . put ( seek , size ) ;
// fill zeros to the content
int l = size ; byte [ ] fill = new byte [ size ] ;
while ( l - - > 0 ) fill [ l ] = 0 ;
this . file . write ( fill , 0 , size ) ;
// remove entry from index
this . index . remove ( key ) ;
// recursively merge gaps
tryMergeNextGaps ( seek , size ) ;
tryMergePreviousGap ( seek ) ;
}
// add entry to free array
this . free . put ( seek , size ) ;
// fill zeros to the content
int l = size ; byte [ ] fill = new byte [ size ] ;
while ( l - - > 0 ) fill [ l ] = 0 ;
this . file . write ( fill , 0 , size ) ;
// remove entry from index
this . index . remove ( key ) ;
// recursively merge gaps
tryMergeNextGaps ( seek , size ) ;
tryMergePreviousGap ( seek ) ;
}
private void tryMergePreviousGap ( final long thisSeek ) throws IOException {
@ -233,66 +235,68 @@ public class HeapModifier extends HeapReader implements BLOB {
throw new UnsupportedOperationException ( "put is not supported in BLOBHeapModifier" ) ;
}
public synchronized int replace ( byte [ ] key , final Rewriter rewriter ) throws IOException {
public int replace ( byte [ ] key , final Rewriter rewriter ) throws IOException {
key = normalizeKey ( key ) ;
assert key . length = = this . keylength ;
// check if the index contains the key
final long pos = index . get ( key ) ;
if ( pos < 0 ) return 0 ;
// check consistency of the index
assert checkKey ( key , pos ) : "key compare failed; key = " + new String ( key ) + ", seek = " + pos ;
// access the file and read the container
file . seek ( pos ) ;
final int len = file . readInt ( ) - this . keylength ;
if ( MemoryControl . available ( ) < len ) {
if ( ! MemoryControl . request ( len , true ) ) return 0 ; // not enough memory available for this blob
}
// read the key
final byte [ ] keyf = new byte [ this . keylength ] ;
file . readFully ( keyf , 0 , keyf . length ) ;
assert this . ordering . equal ( key , keyf ) ;
// read the blob
byte [ ] blob = new byte [ len ] ;
file . readFully ( blob , 0 , blob . length ) ;
// rewrite the entry
blob = rewriter . rewrite ( blob ) ;
int reduction = len - blob . length ;
if ( reduction = = 0 ) {
// even if the reduction is zero then it is still be possible that the record has been changed
this . file . seek ( pos + 4 + key . length ) ;
synchronized ( this ) {
// check if the index contains the key
final long pos = index . get ( key ) ;
if ( pos < 0 ) return 0 ;
// check consistency of the index
assert checkKey ( key , pos ) : "key compare failed; key = " + new String ( key ) + ", seek = " + pos ;
// access the file and read the container
file . seek ( pos ) ;
final int len = file . readInt ( ) - this . keylength ;
if ( MemoryControl . available ( ) < len ) {
if ( ! MemoryControl . request ( len , true ) ) return 0 ; // not enough memory available for this blob
}
// read the key
final byte [ ] keyf = new byte [ this . keylength ] ;
file . readFully ( keyf , 0 , keyf . length ) ;
assert this . ordering . equal ( key , keyf ) ;
// read the blob
byte [ ] blob = new byte [ len ] ;
file . readFully ( blob , 0 , blob . length ) ;
// rewrite the entry
blob = rewriter . rewrite ( blob ) ;
int reduction = len - blob . length ;
if ( reduction = = 0 ) {
// even if the reduction is zero then it is still be possible that the record has been changed
this . file . seek ( pos + 4 + key . length ) ;
file . write ( blob ) ;
return 0 ;
}
// the new entry must be smaller than the old entry and must at least be 4 bytes smaller
// because that is the space needed to write a new empty entry record at the end of the gap
if ( blob . length > len - 4 ) throw new IOException ( "replace of BLOB for key " + new String ( key ) + " failed (too large): new size = " + blob . length + ", old size = " + ( len - 4 ) ) ;
// replace old content
this . file . seek ( pos ) ;
file . writeInt ( blob . length + key . length ) ;
file . write ( key ) ;
file . write ( blob ) ;
return 0 ;
}
// the new entry must be smaller than the old entry and must at least be 4 bytes smaller
// because that is the space needed to write a new empty entry record at the end of the gap
if ( blob . length > len - 4 ) throw new IOException ( "replace of BLOB for key " + new String ( key ) + " failed (too large): new size = " + blob . length + ", old size = " + ( len - 4 ) ) ;
// replace old content
this . file . seek ( pos ) ;
file . writeInt ( blob . length + key . length ) ;
file . write ( key ) ;
file . write ( blob ) ;
// define the new empty entry
final int newfreereclen = reduction - 4 ;
assert newfreereclen > = 0 ;
file . writeInt ( newfreereclen ) ;
// fill zeros to the content
int l = newfreereclen ; byte [ ] fill = new byte [ newfreereclen ] ;
while ( l - - > 0 ) fill [ l ] = 0 ;
this . file . write ( fill , 0 , newfreereclen ) ;
// add a new free entry
this . free . put ( pos + 4 + blob . length + key . length , newfreereclen ) ;
return reduction ;
// define the new empty entry
final int newfreereclen = reduction - 4 ;
assert newfreereclen > = 0 ;
file . writeInt ( newfreereclen ) ;
// fill zeros to the content
int l = newfreereclen ; byte [ ] fill = new byte [ newfreereclen ] ;
while ( l - - > 0 ) fill [ l ] = 0 ;
this . file . write ( fill , 0 , newfreereclen ) ;
// add a new free entry
this . free . put ( pos + 4 + blob . length + key . length , newfreereclen ) ;
return reduction ;
}
}
}
orbiter
15 years ago