Frameworks/base: Compile-time optimize SQLiteConnection

Do not cache compiled regular expression and date formatter. Both
cannot be compile-time created, are expensive at preloading time,
and only used in the rare case of dumping the connection (mainly
on errors).

Bug: 19498458
Bug: 19542228
Change-Id: Ia38491a3f852ccf699b815ff05289b338e932f2a

1 files changed, 10 insertions, 7 deletions

diff --git a/core/java/android/database/sqlite/SQLiteConnection.java b/core/java/android/database/sqlite/SQLiteConnection.java
index 24a7d33..3cda39a 100644
--- a/core/java/android/database/sqlite/SQLiteConnection.java
+++ b/core/java/android/database/sqlite/SQLiteConnection.java
@@ -91,8 +91,6 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
     private static final String[] EMPTY_STRING_ARRAY = new String[0];
     private static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
 
-    private static final Pattern TRIM_SQL_PATTERN = Pattern.compile("[\\s]*\\n+[\\s]*");
-
     private final CloseGuard mCloseGuard = CloseGuard.get();
 
     private final SQLiteConnectionPool mPool;
@@ -1203,7 +1201,11 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
     }
 
     private static String trimSqlForDisplay(String sql) {
-        return TRIM_SQL_PATTERN.matcher(sql).replaceAll(" ");
+        // Note: Creating and caching a regular expression is expensive at preload-time
+        //       and stops compile-time initialization. This pattern is only used when
+        //       dumping the connection, which is a rare (mainly error) case. So:
+        //       DO NOT CACHE.
+        return sql.replaceAll("[\\s]*\\n+[\\s]*", " ");
     }
 
     /**
@@ -1437,9 +1439,6 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
     }
 
     private static final class Operation {
-        private static final SimpleDateFormat sDateFormat =
-                new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
-
         public long mStartTime;
         public long mEndTime;
         public String mKind;
@@ -1494,7 +1493,11 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
         }
 
         private String getFormattedStartTime() {
-            return sDateFormat.format(new Date(mStartTime));
+            // Note: SimpleDateFormat is not thread-safe, cannot be compile-time created, and is
+            //       relatively expensive to create during preloading. This method is only used
+            //       when dumping a connection, which is a rare (mainly error) case. So:
+            //       DO NOT CACHE.
+            return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS").format(new Date(mStartTime));
         }
     }
 }