diff options
Diffstat (limited to 'src/interfaces/jdbc/org/postgresql/PG_Stream.java')
| -rw-r--r-- | src/interfaces/jdbc/org/postgresql/PG_Stream.java | 161 |
1 files changed, 147 insertions, 14 deletions
diff --git a/src/interfaces/jdbc/org/postgresql/PG_Stream.java b/src/interfaces/jdbc/org/postgresql/PG_Stream.java index 22c41bdb3a..0e392fca09 100644 --- a/src/interfaces/jdbc/org/postgresql/PG_Stream.java +++ b/src/interfaces/jdbc/org/postgresql/PG_Stream.java @@ -22,7 +22,10 @@ public class PG_Stream private Socket connection; private InputStream pg_input; private BufferedOutputStream pg_output; - + + public PGStatement executingStatement; + + /** * Constructor: Connect to the PostgreSQL back end and return * a stream connection. @@ -45,6 +48,15 @@ public class PG_Stream } /** + * Set the currently executing statement. This is used to bind cached byte + * arrays to a Statement, so the statement can return the to the global + * pool of unused byte arrays when they are no longer inuse. + */ + public void setExecutingStatement(PGStatement executingStatement){ + this.executingStatement = executingStatement; + } + + /** * Sends a single character to the back end * * @param val the character to be sent @@ -70,7 +82,7 @@ public class PG_Stream */ public void SendInteger(int val, int siz) throws IOException { - byte[] buf = new byte[siz]; + byte[] buf = allocByteDim1(siz); while (siz-- > 0) { @@ -94,7 +106,7 @@ public class PG_Stream */ public void SendIntegerReverse(int val, int siz) throws IOException { - byte[] buf = new byte[siz]; + byte[] buf = allocByteDim1(siz); int p=0; while (siz-- > 0) { @@ -236,23 +248,52 @@ public class PG_Stream return n; } - public String ReceiveString(int maxsize) throws SQLException { - return ReceiveString(maxsize, null); - } - + /** * Receives a null-terminated string from the backend. Maximum of * maxsiz bytes - if we don't see a null, then we assume something * has gone wrong. * + * @param maxsiz maximum length of string + * @return string from back end + * @exception SQLException if an I/O error occurs + */ + public String ReceiveString(int maxsiz) throws SQLException + { + return ReceiveString(maxsiz, null); + } + + /** + * Receives a null-terminated string from the backend. Maximum of + * maxsiz bytes - if we don't see a null, then we assume something + * has gone wrong. + * + * @param maxsiz maximum length of string * @param encoding the charset encoding to use. - * @param maxsiz maximum length of string in bytes * @return string from back end * @exception SQLException if an I/O error occurs */ public String ReceiveString(int maxsiz, String encoding) throws SQLException { - byte[] rst = new byte[maxsiz]; + byte[] rst = allocByteDim1(maxsiz); + return ReceiveString(rst, maxsiz, encoding); + } + + /** + * Receives a null-terminated string from the backend. Maximum of + * maxsiz bytes - if we don't see a null, then we assume something + * has gone wrong. + * + * @param rst byte array to read the String into. rst.length must + * equal to or greater than maxsize. + * @param maxsiz maximum length of string in bytes + * @param encoding the charset encoding to use. + * @return string from back end + * @exception SQLException if an I/O error occurs + */ + public String ReceiveString(byte rst[], int maxsiz, String encoding) + throws SQLException + { int s = 0; try @@ -262,9 +303,10 @@ public class PG_Stream int c = pg_input.read(); if (c < 0) throw new PSQLException("postgresql.stream.eof"); - else if (c == 0) - break; - else + else if (c == 0) { + rst[s] = 0; + break; + } else rst[s++] = (byte)c; } if (s >= maxsiz) @@ -299,7 +341,7 @@ public class PG_Stream { int i, bim = (nf + 7)/8; byte[] bitmask = Receive(bim); - byte[][] answer = new byte[nf][0]; + byte[][] answer = allocByteDim2(nf); int whichbit = 0x80; int whichbyte = 0; @@ -337,7 +379,7 @@ public class PG_Stream */ private byte[] Receive(int siz) throws SQLException { - byte[] answer = new byte[siz]; + byte[] answer = allocByteDim1(siz); Receive(answer,0,siz); return answer; } @@ -395,4 +437,95 @@ public class PG_Stream pg_input.close(); connection.close(); } + + /** + * Deallocate all resources that has been associated with any previous + * query. + */ + public void deallocate(PGStatement stmt){ + + for(int i = 0; i < maxsize_dim1; i++){ + synchronized(notusemap_dim1[i]){ + notusemap_dim1[i].addAll(stmt.inusemap_dim1[i]); + } + stmt.inusemap_dim1[i].clear(); + } + + for(int i = 0; i < maxsize_dim2; i++){ + synchronized(notusemap_dim2[i]){ + notusemap_dim2[i].addAll(stmt.inusemap_dim2[i]); + } + stmt.inusemap_dim2[i].clear(); + } + } + + public static final int maxsize_dim1 = 256; + public static ObjectPool notusemap_dim1[] = new ObjectPool[maxsize_dim1]; + public static byte binit[][] = new byte[maxsize_dim1][0]; + public static final int maxsize_dim2 = 32; + public static ObjectPool notusemap_dim2[] = new ObjectPool[maxsize_dim2]; + public static ObjectPoolFactory factory_dim1; + public static ObjectPoolFactory factory_dim2; + + static { + for(int i = 0; i < maxsize_dim1; i++){ + binit[i] = new byte[i]; + notusemap_dim1[i] = new ObjectPool(); + } + for(int i = 0; i < maxsize_dim2; i++){ + notusemap_dim2[i] = new ObjectPool(); + } + factory_dim1 = ObjectPoolFactory.getInstance(maxsize_dim1); + factory_dim2 = ObjectPoolFactory.getInstance(maxsize_dim2); + } + + public byte[] allocByteDim1(int size){ + if(size >= maxsize_dim1 || executingStatement == null){ + return new byte[size]; + } + ObjectPool not_usel = notusemap_dim1[size]; + ObjectPool in_usel = executingStatement.inusemap_dim1[size]; + + byte b[] = null; + + synchronized(not_usel){ + if(!not_usel.isEmpty()) { + Object o = not_usel.remove(); + b = (byte[]) o; + } else { + b = new byte[size]; + } + } + in_usel.add(b); + + return b; + } + + public byte[][] allocByteDim2(int size){ + if(size >= maxsize_dim2 || executingStatement == null){ + return new byte[size][0]; + } + ObjectPool not_usel = notusemap_dim2[size]; + ObjectPool in_usel = executingStatement.inusemap_dim2[size]; + + byte b[][] = null; + + synchronized(not_usel){ + if(!not_usel.isEmpty()) { + Object o = not_usel.remove(); + b = (byte[][]) o; + } else + b = new byte[size][0]; + + in_usel.add(b); + } + + return b; + } + } + + + + + |