fix messages from sqlite layer in c++ code to be useful.

Change-Id: Ib13f86f3481aae391f5e887bb14877f12bf48034

2 files changed, 13 insertions, 7 deletions

diff --git a/core/jni/android_database_CursorWindow.cpp b/core/jni/android_database_CursorWindow.cpp
index 040dac3..fad9539 100644
--- a/core/jni/android_database_CursorWindow.cpp
+++ b/core/jni/android_database_CursorWindow.cpp
@@ -63,7 +63,8 @@ static void native_init_empty(JNIEnv * env, jobject object, jboolean localOnly)
     }
 
     if (!window->initBuffer(localOnly)) {
-        jniThrowException(env, "java/lang/IllegalStateException", "Couldn't init cursor window");
+        jniThrowException(env, "java/lang/RuntimeException",
+                "Memory couldn't be allocated for 1MB CursorWindow object.");
         delete window;
         return;
     }
@@ -82,11 +83,13 @@ static void native_init_memory(JNIEnv * env, jobject object, jobject memObj)
 
     CursorWindow * window = new CursorWindow();
     if (!window) {
-        jniThrowException(env, "java/lang/RuntimeException", "No memory for native window object");
+        jniThrowException(env, "java/lang/RuntimeException",
+                "CursorWindow of size 1MB couldn't be created. No memory?");
         return;
     }
     if (!window->setMemory(memory)) {
-        jniThrowException(env, "java/lang/RuntimeException", "No memory in memObj");
+        jniThrowException(env, "java/lang/RuntimeException",
+                "Memory couldn't be initialized for 1MB CursorWindow object.");
         delete window;
         return;
     }
@@ -131,8 +134,9 @@ LOG_WINDOW("Closing window %p", window);
 
 static void throwExceptionWithRowCol(JNIEnv * env, jint row, jint column)
 {
-    char buf[100];
-    snprintf(buf, sizeof(buf), "get field slot from row %d col %d failed", row, column);
+    char buf[200];
+    snprintf(buf, sizeof(buf), "Couldn't read row %d, col %d from CursorWindow. Make sure the Cursor is initialized correctly before accessing data from it",
+            row, column);
     jniThrowException(env, "java/lang/IllegalStateException", buf);
 }
 
diff --git a/libs/binder/CursorWindow.cpp b/libs/binder/CursorWindow.cpp
index fbba281..47bbd04 100644
--- a/libs/binder/CursorWindow.cpp
+++ b/libs/binder/CursorWindow.cpp
@@ -219,7 +219,8 @@ LOG_WINDOW("follwing 'pointer' to next chunk, offset of next pointer is %d", chu
 field_slot_t * CursorWindow::getFieldSlotWithCheck(int row, int column)
 {
   if (row < 0 || row >= mHeader->numRows || column < 0 || column >= mHeader->numColumns) {
-      LOGE("Bad request for field slot %d,%d. numRows = %d, numColumns = %d", row, column, mHeader->numRows, mHeader->numColumns);
+      LOGE("Failed to read row# %d, column# from a CursorWindow which has %d rows, %d columns.",
+              row, column, mHeader->numRows, mHeader->numColumns);
       return NULL;
   }        
   row_slot_t * rowSlot = getRowSlot(row);
@@ -238,7 +239,8 @@ field_slot_t * CursorWindow::getFieldSlotWithCheck(int row, int column)
 uint32_t CursorWindow::read_field_slot(int row, int column, field_slot_t * slotOut)
 {
     if (row < 0 || row >= mHeader->numRows || column < 0 || column >= mHeader->numColumns) {
-        LOGE("Bad request for field slot %d,%d. numRows = %d, numColumns = %d", row, column, mHeader->numRows, mHeader->numColumns);
+        LOGE("Can't read row# %d, col# %d from CursorWindow. Make sure your Cursor is initialized correctly.",
+                row, column);
         return -1;
     }        
     row_slot_t * rowSlot = getRowSlot(row);