Utils.writeLong

h2/src/main/org/h2/util/Utils.java

@@ -63,6 +63,26 @@ public class Utils {
         return (buff[pos++] << 24) + ((buff[pos++] & 0xff) << 16) + ((buff[pos++] & 0xff) << 8) + (buff[pos] & 0xff);
     }
 
+    /**
+     * Write a long value to the byte array at the given position. The most
+     * significant byte is written first.
+     *
+     * @param buff the byte array
+     * @param pos the position
+     * @param x the value to write
+     */
+    public static void writeLong(byte[] buff, int pos, long x) {
+        writeInt(buff, pos, (int) (x >> 32));
+        writeInt(buff, pos + 4, (int) x);
+    }
+
+    private static void writeInt(byte[] buff, int pos, int x) {
+        buff[pos++] = (byte) (x >> 24);
+        buff[pos++] = (byte) (x >> 16);
+        buff[pos++] = (byte) (x >> 8);
+        buff[pos++] = (byte) x;
+    }
+
     /**
      * Read a long value from the byte array at the given position. The most
      * significant byte is read first.

h2/src/test/org/h2/test/unit/TestUtils.java

@@ -8,6 +8,7 @@ package org.h2.test.unit;
 
 import java.io.File;
 import java.math.BigInteger;
+import java.util.Random;
 import org.h2.test.TestBase;
 import org.h2.util.Utils;
 
@@ -31,12 +32,30 @@ public class TestUtils extends TestBase {
     }
 
     public void test() throws Exception {
+        testWriteReadLong();
         testGetNonPrimitiveClass();
         testGetNonPrimitiveClass();
         testGetNonPrimitiveClass();
         testReflectionUtils();
     }
 
+    private void testWriteReadLong() {
+        byte[] buff = new byte[8];
+        for (long x : new long[]{Long.MIN_VALUE, Long.MAX_VALUE, 0, 1, -1,
+                Integer.MIN_VALUE, Integer.MAX_VALUE}) {
+            Utils.writeLong(buff, 0, x);
+            long y = Utils.readLong(buff, 0);
+            assertEquals(x, y);
+        }
+        Random r = new Random(1);
+        for (int i = 0; i < 1000; i++) {
+            long x = r.nextLong();
+            Utils.writeLong(buff, 0, x);
+            long y = Utils.readLong(buff, 0);
+            assertEquals(x, y);
+        }
+    }
+
     private void testGetNonPrimitiveClass() throws Exception {
         testGetNonPrimitiveClass(BigInteger.class, BigInteger.class);
         testGetNonPrimitiveClass(Boolean.class, boolean.class);