From fe0aabcd8d03d5e61e182494d222ccb47bf30bb7 Mon Sep 17 00:00:00 2001
From: sebastien-doyon <sebastiendn@gmail.com>
Date: Tue, 26 Sep 2023 15:36:00 +0200
Subject: [PATCH] [MNG-7899] Various memory usage improvements

Merging the getStatus() method to optimize :

- Use the main StringBuilder to append string instead of using a
separate one
- Use the StringBuilder.append() with index to avoid String.substring(),
less temporary strings
- Reuse the FileSizeFormat object in the while loop avoiding multiple
temporary instances creation
---
 .../ConsoleMavenTransferListener.java         | 44 ++++++++++---------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/maven-embedder/src/main/java/org/apache/maven/cli/transfer/ConsoleMavenTransferListener.java b/maven-embedder/src/main/java/org/apache/maven/cli/transfer/ConsoleMavenTransferListener.java
index a0045f712a7c..c7b132adc5b6 100644
--- a/maven-embedder/src/main/java/org/apache/maven/cli/transfer/ConsoleMavenTransferListener.java
+++ b/maven-embedder/src/main/java/org/apache/maven/cli/transfer/ConsoleMavenTransferListener.java
@@ -68,13 +68,34 @@ public synchronized void transferProgressed(TransferEvent event) throws Transfer
         buffer.append("Progress (").append(transfers.size()).append("): ");
 
         synchronized (transfers) {
+            FileSizeFormat format = new FileSizeFormat(Locale.ENGLISH);
+
             Iterator<Map.Entry<TransferResource, Long>> entries =
                     transfers.entrySet().iterator();
             while (entries.hasNext()) {
                 Map.Entry<TransferResource, Long> entry = entries.next();
                 long total = entry.getKey().getContentLength();
                 Long complete = entry.getValue();
-                buffer.append(getStatus(entry.getKey().getResourceName(), complete, total));
+
+                String resourceName = entry.getKey().getResourceName();
+
+                if (printResourceNames) {
+                    int idx = resourceName.lastIndexOf('/');
+
+                    if (idx < 0) {
+                        buffer.append(resourceName);
+                    } else {
+                        buffer.append(resourceName, idx + 1, resourceName.length());
+                    }
+                    buffer.append(" (");
+                }
+
+                buffer.append(format.formatProgress(complete, total));
+
+                if (printResourceNames) {
+                    buffer.append(")");
+                }
+
                 if (entries.hasNext()) {
                     buffer.append(" | ");
                 }
@@ -89,25 +110,6 @@ public synchronized void transferProgressed(TransferEvent event) throws Transfer
         out.flush();
     }
 
-    private String getStatus(String resourceName, long complete, long total) {
-        FileSizeFormat format = new FileSizeFormat(Locale.ENGLISH);
-        StringBuilder status = new StringBuilder();
-
-        if (printResourceNames) {
-            int idx = resourceName.lastIndexOf('/');
-            status.append(idx < 0 ? resourceName : resourceName.substring(idx + 1));
-            status.append(" (");
-        }
-
-        status.append(format.formatProgress(complete, total));
-
-        if (printResourceNames) {
-            status.append(")");
-        }
-
-        return status.toString();
-    }
-
     private void pad(StringBuilder buffer, int spaces) {
         String block = "                                        ";
         while (spaces > 0) {
@@ -135,7 +137,7 @@ public synchronized void transferFailed(TransferEvent event) {
 
     private void overridePreviousTransfer(TransferEvent event) {
         if (lastLength > 0) {
-            StringBuilder buffer = new StringBuilder(128);
+            StringBuilder buffer = new StringBuilder(lastLength + 1);
             pad(buffer, lastLength);
             buffer.append('\r');
             out.print(buffer);