From b8f1bb92236b24c5e2ede180feeab0a2f2eee1e4 Mon Sep 17 00:00:00 2001
From: Abhinav Gupta <mail@abhinavg.net>
Date: Tue, 27 Sep 2011 18:15:21 +0000
Subject: [PATCH] ICU-8268 concatenation of strings using + in a loop is
 inefficient. Use StringBuilder.

X-SVN-Rev: 30720
---
 .../com/ibm/icu/text/DateTimePatternGenerator.java  | 13 ++++++++-----
 .../core/src/com/ibm/icu/text/RBBIDataWrapper.java  |  6 +++---
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/icu4j/main/classes/core/src/com/ibm/icu/text/DateTimePatternGenerator.java b/icu4j/main/classes/core/src/com/ibm/icu/text/DateTimePatternGenerator.java
index 3cf27bade0b..11719a92cfe 100644
--- a/icu4j/main/classes/core/src/com/ibm/icu/text/DateTimePatternGenerator.java
+++ b/icu4j/main/classes/core/src/com/ibm/icu/text/DateTimePatternGenerator.java
@@ -1756,13 +1756,16 @@ public class DateTimePatternGenerator implements Freezable<DateTimePatternGenera
     }
 
     private static String showMask(int mask) {
-        String result = "";
+        StringBuilder result = new StringBuilder();
         for (int i = 0; i < TYPE_LIMIT; ++i) {
-            if ((mask & (1<<i)) == 0) continue;
-            if (result.length() != 0) result += " | ";
-            result += FIELD_NAME[i] + " ";
+            if ((mask & (1<<i)) == 0)
+                continue;
+            if (result.length() != 0)
+                result.append(" | ");
+            result.append(FIELD_NAME[i]);
+            result.append(" ");
         }
-        return result;
+        return result.toString();
     }
 
     static private String[] CLDR_FIELD_APPEND = {
diff --git a/icu4j/main/classes/core/src/com/ibm/icu/text/RBBIDataWrapper.java b/icu4j/main/classes/core/src/com/ibm/icu/text/RBBIDataWrapper.java
index 357fb74236e..046061aee57 100644
--- a/icu4j/main/classes/core/src/com/ibm/icu/text/RBBIDataWrapper.java
+++ b/icu4j/main/classes/core/src/com/ibm/icu/text/RBBIDataWrapper.java
@@ -384,11 +384,11 @@ final class RBBIDataWrapper {
         } else {
             int n;
             int state;
-            String header = " Row  Acc Look  Tag";
+            StringBuilder header = new StringBuilder(" Row  Acc Look  Tag");
             for (n=0; n<fHeader.fCatCount; n++) {
-                header += intToString(n, 5);     
+                header.append(intToString(n, 5));
             }
-            System.out.println(header);
+            System.out.println(header.toString());
             for (n=0; n<header.length(); n++) {
                 System.out.print("-");
             }
-- 
2.40.0