Warnings fixed

GitOrigin-RevId: feabd51d4f4c25bfc769b22d3847294e202f2462

java/java-impl/src/com/intellij/ide/util/treeView/TreeViewUtil.java

@@ -78,7 +78,7 @@ public class TreeViewUtil {
       }
       name.insert(0, ".");
       if (packageName.length() > 2 && shouldAbbreviateName(parentPackage)) {
-        name.insert(0, packageName.substring(0, 1));
+        name.insert(0, packageName.charAt(0));
       }
       else {
         name.insert(0, packageName);

platform/platform-impl/src/com/intellij/util/ui/SwingHelper.java

@@ -367,7 +367,7 @@ public class SwingHelper {
     }
   }
 
-  public static void setLongestAsPrototype(@NotNull JComboBox comboBox, @NotNull List<String> variants) {
+  private static void setLongestAsPrototype(@NotNull JComboBox comboBox, @NotNull List<String> variants) {
     Object prototypeDisplayValue = comboBox.getPrototypeDisplayValue();
     String prototypeDisplayValueStr = null;
     if (prototypeDisplayValue instanceof String) {
@@ -724,15 +724,14 @@ public class SwingHelper {
     final String currentSubstring = text.substring(0, currentLen);
     int realWidth = fm.stringWidth(currentSubstring);
 
+    int delta = 0;
     if (realWidth >= availableWidth) {
-      int delta = 0;
       for (int i = currentLen - 1; i >= 0; i--) {
         if ((realWidth - delta) < availableWidth) return text.substring(0, i) + ELLIPSIS;
         delta += fm.charWidth(currentSubstring.charAt(i));
       }
-      return text.substring(0, 1) + ELLIPSIS;
+      return text.charAt(0) + ELLIPSIS;
     } else {
-      int delta = 0;
       for (int i = currentLen; i < text.length(); i++) {
         if ((realWidth + delta) >= availableWidth) return text.substring(0, i) + ELLIPSIS;
         delta += fm.charWidth(text.charAt(i));

plugins/git4idea/rt/src/git4idea/rebase/GitRebaseEditorMain.java

@@ -75,7 +75,7 @@ public class GitRebaseEditorMain implements GitExternalApp {
       params.add(handlerId);
       if (System.getProperty("os.name").toLowerCase(Locale.ENGLISH).startsWith("windows") && file.startsWith(CYGDRIVE_PREFIX)) {
         int p = CYGDRIVE_PREFIX.length();
-        file = file.substring(p, p + 1) + ":" + file.substring(p + 1);
+        file = file.charAt(p) + ":" + file.substring(p + 1);
       }
       params.add(new File(file).getAbsolutePath());
       Integer exitCode = (Integer)client.execute(HANDLER_NAME + ".editCommits", params);

plugins/git4idea/src/git4idea/rebase/GitInteractiveRebaseFile.java

@@ -85,7 +85,7 @@ class GitInteractiveRebaseFile {
   private static String adjustFilePath(@NotNull String file) {
     if (SystemInfo.isWindows && file.startsWith(CYGDRIVE_PREFIX)) {
       final int prefixSize = CYGDRIVE_PREFIX.length();
-      return file.substring(prefixSize, prefixSize + 1) + ":" + file.substring(prefixSize + 1);
+      return file.charAt(prefixSize) + ":" + file.substring(prefixSize + 1);
     }
     return file;
   }

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/codeInspection/confusing/GrUnusedIncDecInspection.java

@@ -173,7 +173,7 @@ public class GrUnusedIncDecInspection extends BaseInspection {
       public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
         GrUnaryExpression expr = findUnaryExpression(descriptor);
         GrExpression newExpr = GroovyPsiElementFactory.getInstance(project)
-          .createExpressionFromText(expr.getOperand().getText() + expr.getOperationToken().getText().substring(0, 1) + "1");
+          .createExpressionFromText(expr.getOperand().getText() + expr.getOperationToken().getText().charAt(0) + "1");
         expr.replaceWithExpression(newExpr, true);
       }
     }