String patch

gistfile1.txt

Index: src/java.base/share/classes/java/lang/AbstractStringBuilder.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/java.base/share/classes/java/lang/AbstractStringBuilder.java b/src/java.base/share/classes/java/lang/AbstractStringBuilder.java
--- a/src/java.base/share/classes/java/lang/AbstractStringBuilder.java	(revision 674fa32cf8403ceec84bbe2c3f9404d612c10797)
+++ b/src/java.base/share/classes/java/lang/AbstractStringBuilder.java	(date 1674682743075)
@@ -1680,8 +1680,8 @@
                 return;
             }
         }
-        this.coder = UTF16;
         this.value = StringUTF16.toBytes(value, off, len);
+        this.coder = value.length == len ? LATIN1 : UTF16;;
     }
 
     final byte getCoder() {
Index: src/java.base/share/classes/java/lang/StringUTF16.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/java.base/share/classes/java/lang/StringUTF16.java b/src/java.base/share/classes/java/lang/StringUTF16.java
--- a/src/java.base/share/classes/java/lang/StringUTF16.java	(revision 674fa32cf8403ceec84bbe2c3f9404d612c10797)
+++ b/src/java.base/share/classes/java/lang/StringUTF16.java	(date 1689147746269)
@@ -25,9 +25,7 @@
 
 package java.lang;
 
-import java.util.Arrays;
-import java.util.Locale;
-import java.util.Spliterator;
+import java.util.*;
 import java.util.function.Consumer;
 import java.util.function.IntConsumer;
 import java.util.stream.Stream;
@@ -150,10 +148,16 @@
     @IntrinsicCandidate
     public static byte[] toBytes(char[] value, int off, int len) {
         byte[] val = newBytesFor(len);
+        boolean hasNonLatin1 = false;
         for (int i = 0; i < len; i++) {
-            putChar(val, i, value[off]);
+            char c = value[off];
+            hasNonLatin1 |= c > 0xFF;
+            putChar(val, i, c);
             off++;
         }
+        if (!hasNonLatin1) {
+            return Objects.requireNonNull(compress(val, 0, len));
+        }
         return val;
     }
 
Index: src/java.base/share/classes/java/lang/String.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/src/java.base/share/classes/java/lang/String.java b/src/java.base/share/classes/java/lang/String.java
--- a/src/java.base/share/classes/java/lang/String.java	(revision 674fa32cf8403ceec84bbe2c3f9404d612c10797)
+++ b/src/java.base/share/classes/java/lang/String.java	(date 1677570581400)
@@ -660,8 +660,8 @@
                         return;
                     }
                 }
-                coder = UTF16;
                 value = StringUTF16.toBytes(ca, 0, clen);
+                coder = value.length == clen ? LATIN1 : UTF16;
                 return;
             }
 
@@ -691,8 +691,8 @@
                     return;
                 }
             }
-            coder = UTF16;
             value = StringUTF16.toBytes(ca, 0, caLen);
+            coder = value.length == caLen ? LATIN1 : UTF16;
         }
     }
 
@@ -821,7 +821,8 @@
                 return new String(bs, LATIN1);
             }
         }
-        return new String(StringUTF16.toBytes(ca, 0, caLen), UTF16);
+        byte[] bytes = StringUTF16.toBytes(ca, 0, caLen);
+        return new String(bytes, bytes.length == caLen ? LATIN1 : UTF16);
     }
 
     private static final char REPL = '\ufffd';
@@ -4523,8 +4524,8 @@
                 return;
             }
         }
-        this.coder = UTF16;
         this.value = StringUTF16.toBytes(value, off, len);
+        this.coder = value.length == len ? LATIN1 : UTF16;;
     }
 
     /*