From 3862b9e8197e3fc5eeb615453066752f49d62dc1 Mon Sep 17 00:00:00 2001
From: Jean Chalard <jchalard@google.com>
Date: Thu, 25 Oct 2012 16:28:17 +0900
Subject: [PATCH] Add symmetry and pre-emptively improve performance (A4)

The test for binary dictionary will soon entail decrypting and
uncompressing files if necessary to test for their headers, and will
become much slower than it is. It's better to be able to detect the
XML format too, and leave the slower test for last.

Bug: 7388852
Change-Id: I6b9a7944de80217e1571cab65dcd1cff347b3046
---
 .../latin/dicttool/DictionaryMaker.java       |  9 +++--
 .../latin/dicttool/XmlDictInputOutput.java    | 33 +++++++++++++++++++
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
index 561db7363..cc890f60c 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/DictionaryMaker.java
@@ -172,12 +172,15 @@ public class DictionaryMaker {
                         String filename = args.get(0);
                         args.remove(0);
                         if (OPTION_INPUT_SOURCE.equals(arg)) {
-                            if (BinaryDictInputOutput.isBinaryDictionary(filename)) {
-                                inputBinary = filename;
+                            if (XmlDictInputOutput.isXmlUnigramDictionary(filename)) {
+                                inputUnigramXml = filename;
                             } else if (CombinedInputOutput.isCombinedDictionary(filename)) {
                                 inputCombined = filename;
+                            } else if (BinaryDictInputOutput.isBinaryDictionary(filename)) {
+                                inputBinary = filename;
                             } else {
-                                inputUnigramXml = filename;
+                                throw new IllegalArgumentException(
+                                        "Unknown format for file " + filename);
                             }
                         } else if (OPTION_INPUT_SHORTCUT_XML.equals(arg)) {
                             inputShortcutXml = filename;
diff --git a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
index 252c3d655..d8d94a13c 100644
--- a/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
+++ b/tools/dicttool/src/com/android/inputmethod/latin/dicttool/XmlDictInputOutput.java
@@ -22,6 +22,10 @@ import com.android.inputmethod.latin.makedict.FusionDictionary.Node;
 import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
 import com.android.inputmethod.latin.makedict.Word;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Writer;
@@ -263,6 +267,35 @@ public class XmlDictInputOutput {
         }
     }
 
+    /**
+     * Basic test to find out whether the file is in the unigram XML format or not.
+     *
+     * Concretely this only tests the header line.
+     *
+     * @param filename The name of the file to test.
+     * @return true if the file is in the unigram XML format, false otherwise
+     */
+    public static boolean isXmlUnigramDictionary(final String filename) {
+        BufferedReader reader = null;
+        try {
+            reader = new BufferedReader(new FileReader(new File(filename)));
+            final String firstLine = reader.readLine();
+            return firstLine.matches("^\\s*<wordlist .*>\\s*$");
+        } catch (FileNotFoundException e) {
+            return false;
+        } catch (IOException e) {
+            return false;
+        } finally {
+            if (reader != null) {
+                try {
+                    reader.close();
+                } catch (IOException e) {
+                    // do nothing
+                }
+            }
+        }
+    }
+
     /**
      * Reads a dictionary from an XML file.
      *