postgresql-jdbc.git / summary / log / commit / refs

commit    1764c90f12c9ed864b94de742ec71185f4d779b2
Author:   Alexis Meneses <alexismeneses@users.noreply.github.com>
Date:     Sun Nov 23 19:47:17 2014 +0000

    Added support for jdbc4 Blob.getBinaryStream(long,long)


 org/postgresql/jdbc4/AbstractJdbc4Blob.java     | 14 ++++++++-
 org/postgresql/largeobject/BlobInputStream.java | 27 ++++++++++++++++
 org/postgresql/largeobject/LargeObject.java     | 11 +++++++
 org/postgresql/test/jdbc4/BlobTest.java         | 42 +++++++++++++++++++++++++
 4 files changed, 93 insertions(+), 1 deletion(-)

diff --git a/org/postgresql/jdbc4/AbstractJdbc4Blob.java b/org/postgresql/jdbc4/AbstractJdbc4Blob.java
index 8e2fc557..f422dd2e 100644
--- a/org/postgresql/jdbc4/AbstractJdbc4Blob.java
+++ b/org/postgresql/jdbc4/AbstractJdbc4Blob.java
@@ -10,6 +10,8 @@ package org.postgresql.jdbc4;
 
 import java.sql.*;
 
+import org.postgresql.largeobject.LargeObject;
+
 public abstract class AbstractJdbc4Blob extends org.postgresql.jdbc3.AbstractJdbc3Blob
 {
 
@@ -21,7 +23,17 @@ public abstract class AbstractJdbc4Blob extends org.postgresql.jdbc3.AbstractJdb
     public synchronized java.io.InputStream getBinaryStream(long pos, long length) throws SQLException
     {
         checkFreed();
-        throw org.postgresql.Driver.notImplemented(this.getClass(), "getBinaryStream(long, long)");
+        LargeObject subLO = getLo(false).copy();
+        addSubLO(subLO);
+        if (pos > Integer.MAX_VALUE)
+        {
+            subLO.seek64(pos - 1, LargeObject.SEEK_SET);
+        }
+        else
+        {
+            subLO.seek((int) pos - 1, LargeObject.SEEK_SET);
+        }
+        return subLO.getInputStream(length);
     }
 
 }
diff --git a/org/postgresql/largeobject/BlobInputStream.java b/org/postgresql/largeobject/BlobInputStream.java
index 8d128d80..d0ec4610 100644
--- a/org/postgresql/largeobject/BlobInputStream.java
+++ b/org/postgresql/largeobject/BlobInputStream.java
@@ -21,6 +21,11 @@ public class BlobInputStream extends InputStream
      */
     private LargeObject lo;
 
+    /**
+     * The absolute position
+     */
+    private long apos;
+
     /**
      * Buffer used to improve performance
      */
@@ -41,6 +46,11 @@ public class BlobInputStream extends InputStream
      */
     private int mpos = 0;
 
+    /**
+     * The limit
+     */
+    private long limit = -1;
+
     /**
      * @param lo LargeObject to read from
      */
@@ -53,12 +63,24 @@ public class BlobInputStream extends InputStream
      * @param lo LargeObject to read from
      * @param bsize buffer size
      */
+
     public BlobInputStream(LargeObject lo, int bsize)
+    {
+        this(lo, 1024, -1);
+    }
+
+    /**
+     * @param lo LargeObject to read from
+     * @param bsize buffer size
+     */
+    public BlobInputStream(LargeObject lo, int bsize, long limit)
     {
         this.lo = lo;
         buffer = null;
         bpos = 0;
+        apos = 0;
         this.bsize = bsize;
+        this.limit = limit;
     }
 
     /**
@@ -69,6 +91,10 @@ public class BlobInputStream extends InputStream
         checkClosed();
         try
         {
+            if (limit > 0 && apos >= limit)
+            {
+                return -1;
+            }
             if (buffer == null || bpos >= buffer.length)
             {
                 buffer = lo.read(bsize);
@@ -88,6 +114,7 @@ public class BlobInputStream extends InputStream
             }
 
             bpos++;
+            apos++;
 
             return ret;
         }
diff --git a/org/postgresql/largeobject/LargeObject.java b/org/postgresql/largeobject/LargeObject.java
index 8a2928a4..324fc9b0 100644
--- a/org/postgresql/largeobject/LargeObject.java
+++ b/org/postgresql/largeobject/LargeObject.java
@@ -410,6 +410,17 @@ public class LargeObject
         return new BlobInputStream(this, 4096);
     }
 
+    /**
+     * Returns an InputStream from this object, that will limit the amount of data that is visible
+     *
+     * @param limit maximum number of bytes the resulting stream will serve
+     * @exception SQLException if a database-access error occurs.
+     */
+    public InputStream getInputStream(long limit) throws SQLException
+    {
+        return new BlobInputStream(this, 4096, limit);
+    }
+
     /**
      * Returns an OutputStream to this object.
      *
diff --git a/org/postgresql/test/jdbc4/BlobTest.java b/org/postgresql/test/jdbc4/BlobTest.java
index 6b91ce83..4e1e1a7d 100644
--- a/org/postgresql/test/jdbc4/BlobTest.java
+++ b/org/postgresql/test/jdbc4/BlobTest.java
@@ -1,6 +1,7 @@
 package org.postgresql.test.jdbc4;
 
 import java.io.ByteArrayInputStream;
+import java.io.InputStream;
 import java.sql.Blob;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
@@ -97,4 +98,45 @@ public class BlobTest extends TestCase
             selectStmt.close();
         }
     }
+
+    public void testGetBinaryStreamWithBoundaries() throws Exception
+    {
+        byte[] data = new String("Cras vestibulum tellus eu sapien imperdiet ornare.").getBytes("UTF-8");
+        PreparedStatement insertPS = _conn.prepareStatement(TestUtil.insertSQL("testblob", "lo", "?"));
+        try
+        {
+            insertPS.setBlob(1, new ByteArrayInputStream(data), data.length);
+            insertPS.executeUpdate();
+        }
+        finally
+        {
+            insertPS.close();
+        }
+
+        Statement selectStmt = _conn.createStatement();
+        try
+        {
+            ResultSet rs = selectStmt.executeQuery(TestUtil.selectSQL("testblob", "lo"));
+            assertTrue(rs.next());
+    
+            byte[] actualData = new byte[10];
+            Blob actualBlob = rs.getBlob(1);
+            InputStream stream = actualBlob.getBinaryStream(6, 10);
+            try
+            {
+                stream.read(actualData);
+                Assert.assertEquals("Stream should be at end", -1, stream.read(new byte[1]));
+            }
+            finally
+            {
+                stream.close();
+            }
+            Assert.assertEquals("vestibulum", new String(actualData, "UTF-8"));
+        }
+        finally
+        {
+            selectStmt.close();
+        }
+    }
+
 }


[parent: 27397a24d3fd]