Use StringBuilder instead of StringBuffer (#10154)

buildhelpers/src/main/java/com/vaadin/buildhelpers/CompileTheme.java

@@ -91,7 +91,7 @@ public class CompileTheme {
     private static void processSassTheme(String themeFolder, String themeName,
             String variant, String version) throws Exception {
 
-        StringBuffer cssHeader = new StringBuffer();
+        StringBuilder cssHeader = new StringBuilder();
 
         String stylesCssDir = themeFolder + File.separator + themeName
                 + File.separator;

buildhelpers/src/main/java/com/vaadin/buildhelpers/ManifestWriter.java

@@ -26,7 +26,7 @@ import java.util.Date;
 import java.util.jar.Manifest;
 
 public class ManifestWriter {
-    StringBuffer buffer = new StringBuffer();
+    StringBuilder buffer = new StringBuilder();
 
     public ManifestWriter() {
     }

client/src/main/java/com/vaadin/client/ui/Action.java

@@ -40,7 +40,7 @@ public abstract class Action implements Command {
     public abstract void execute();
 
     public String getHTML() {
-        final StringBuffer sb = new StringBuffer();
+        final StringBuilder sb = new StringBuilder();
         sb.append("<div>");
         // Could store the icon in a field instead, but it doesn't really matter
         // right now because Actions are recreated every time they are needed

client/src/main/java/com/vaadin/client/ui/VComboBox.java

@@ -136,7 +136,7 @@ public class VComboBox extends Composite implements Field, KeyDownHandler,
 
         @Override
         public String getDisplayString() {
-            final StringBuffer sb = new StringBuffer();
+            final StringBuilder sb = new StringBuilder();
             ApplicationConnection client = connector.getConnection();
             final Icon icon = client
                     .getIcon(client.translateVaadinUri(untranslatedIconUri));

client/src/main/java/com/vaadin/client/ui/VMenuBar.java

@@ -220,7 +220,7 @@ public class VMenuBar extends SimpleFocusablePanel
      */
     public String buildItemHTML(UIDL item) {
         // Construct html from the text and the optional icon
-        StringBuffer itemHTML = new StringBuffer();
+        StringBuilder itemHTML = new StringBuilder();
         if (item.hasAttribute("separator")) {
             itemHTML.append("<span>---</span>");
         } else {

client/src/main/java/com/vaadin/client/ui/menubar/MenuBarConnector.java

@@ -73,7 +73,7 @@ public class MenuBarConnector extends AbstractComponentConnector
         if (null != getState()
                 && !ComponentStateUtil.isUndefinedWidth(getState())) {
             UIDL moreItemUIDL = options.getChildUIDL(0);
-            StringBuffer itemHTML = new StringBuffer();
+            StringBuilder itemHTML = new StringBuilder();
 
             if (moreItemUIDL.hasAttribute("icon")) {
                 Icon icon = client

client/src/main/java/com/vaadin/client/ui/popupview/PopupViewConnector.java

@@ -102,7 +102,7 @@ public class PopupViewConnector extends AbstractHasComponentsConnector
             getWidget().preparePopup(getWidget().popup);
             getWidget().popup.setPopupConnector(getChildComponents().get(0));
 
-            final StringBuffer styleBuf = new StringBuffer();
+            final StringBuilder styleBuf = new StringBuilder();
             final String primaryName = getWidget().popup.getStylePrimaryName();
             styleBuf.append(primaryName);
 

client/src/main/java/com/vaadin/client/widgets/Grid.java

@@ -4081,7 +4081,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
         }
 
         private String createHTML(Column<?, T> column) {
-            final StringBuffer buf = new StringBuffer();
+            final StringBuilder buf = new StringBuilder();
             buf.append("<span class=\"");
             if (column.isHidden()) {
                 buf.append("v-off");

compatibility-client/src/main/java/com/vaadin/v7/client/ui/VFilterSelect.java

@@ -136,7 +136,7 @@ public class VFilterSelect extends Composite
 
         @Override
         public String getDisplayString() {
-            final StringBuffer sb = new StringBuffer();
+            final StringBuilder sb = new StringBuilder();
             final Icon icon = client
                     .getIcon(client.translateVaadinUri(untranslatedIconUri));
             if (icon != null) {

compatibility-client/src/main/java/com/vaadin/v7/client/ui/VScrollTable.java

@@ -3987,7 +3987,7 @@ public class VScrollTable extends FlowPanel
 
             @Override
             public String getHTML() {
-                final StringBuffer buf = new StringBuffer();
+                final StringBuilder buf = new StringBuilder();
                 buf.append("<span class=\"");
                 if (collapsed) {
                     buf.append("v-off");

compatibility-client/src/main/java/com/vaadin/v7/client/widgets/Grid.java

@@ -4048,7 +4048,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
         }
 
         private String createHTML(Column<?, T> column) {
-            final StringBuffer buf = new StringBuffer();
+            final StringBuilder buf = new StringBuilder();
             buf.append("<span class=\"");
             if (column.isHidden()) {
                 buf.append("v-off");

compatibility-server/src/main/java/com/vaadin/v7/data/util/sqlcontainer/RowItem.java

@@ -125,7 +125,7 @@ public final class RowItem implements Item {
 
     @Override
     public String toString() {
-        StringBuffer s = new StringBuffer();
+        StringBuilder s = new StringBuilder();
         s.append("ID:");
         s.append(getId().toString());
         for (Object propId : getItemPropertyIds()) {

compatibility-server/src/main/java/com/vaadin/v7/data/util/sqlcontainer/query/FreeformQuery.java

@@ -465,7 +465,7 @@ public class FreeformQuery extends AbstractTransactionalQuery
 
     private String modifyWhereClause(Object... keys) {
         // Build the where rules for the provided keys
-        StringBuffer where = new StringBuffer();
+        StringBuilder where = new StringBuilder();
         for (int ix = 0; ix < primaryKeyColumns.size(); ix++) {
             where.append(QueryBuilder.quote(primaryKeyColumns.get(ix)));
             if (keys[ix] == null) {

compatibility-server/src/main/java/com/vaadin/v7/data/util/sqlcontainer/query/generator/DefaultSQLGenerator.java

@@ -137,7 +137,7 @@ public class DefaultSQLGenerator implements SQLGenerator {
             throw new IllegalArgumentException("Updated item must be given.");
         }
         StatementHelper sh = getStatementHelper();
-        StringBuffer query = new StringBuffer();
+        StringBuilder query = new StringBuilder();
         query.append("UPDATE ").append(tableName).append(" SET");
 
         /* Generate column<->value and rowidentifiers map */
@@ -191,7 +191,7 @@ public class DefaultSQLGenerator implements SQLGenerator {
                     "Cannot generate an insert query for item already in database.");
         }
         StatementHelper sh = getStatementHelper();
-        StringBuffer query = new StringBuffer();
+        StringBuilder query = new StringBuilder();
         query.append("INSERT INTO ").append(tableName).append(" (");
 
         /* Generate column<->value map */
@@ -246,7 +246,7 @@ public class DefaultSQLGenerator implements SQLGenerator {
                     "Valid keyColumnNames must be provided.");
         }
         StatementHelper sh = getStatementHelper();
-        StringBuffer query = new StringBuffer();
+        StringBuilder query = new StringBuilder();
         query.append("DELETE FROM ").append(tableName).append(" WHERE ");
         int count = 1;
         for (String keyColName : primaryKeyColumns) {

compatibility-server/src/main/java/com/vaadin/v7/ui/Label.java

@@ -505,7 +505,7 @@ public class Label extends AbstractLegacyComponent implements Property<String>,
      */
     private String stripTags(String xml) {
 
-        final StringBuffer res = new StringBuffer();
+        final StringBuilder res = new StringBuilder();
 
         int processed = 0;
         final int xmlLen = xml.length();

compatibility-server/src/test/java/com/vaadin/v7/data/util/sqlcontainer/SQLContainerTest.java

@@ -1705,7 +1705,7 @@ public class SQLContainerTest {
                                         .getQueryString();
                             }
                         } else {
-                            StringBuffer query = new StringBuffer(
+                            StringBuilder query = new StringBuilder(
                                     "SELECT * FROM people");
                             if (!orderBys.isEmpty()) {
                                 query.append(" ORDER BY ");
@@ -1823,7 +1823,7 @@ public class SQLContainerTest {
                                         .getQueryString();
                             }
                         } else {
-                            StringBuffer query = new StringBuffer(
+                            StringBuilder query = new StringBuilder(
                                     "SELECT * FROM people");
                             if (!orderBys.isEmpty()) {
                                 query.append(" ORDER BY ");
@@ -1911,7 +1911,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -1982,7 +1982,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -2052,7 +2052,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -2123,7 +2123,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -2200,7 +2200,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -2277,7 +2277,7 @@ public class SQLContainerTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder
@@ -2408,7 +2408,7 @@ public class SQLContainerTest {
                                         .getQueryString();
                             }
                         } else {
-                            StringBuffer query = new StringBuffer(
+                            StringBuilder query = new StringBuilder(
                                     "SELECT * FROM people");
                             if (!orderBys.isEmpty()) {
                                 query.append(" ORDER BY ");

compatibility-server/src/test/java/com/vaadin/v7/data/util/sqlcontainer/TicketTest.java

@@ -92,7 +92,7 @@ public class TicketTest {
                     @Override
                     public StatementHelper answer() throws Throwable {
                         StatementHelper sh = new StatementHelper();
-                        StringBuffer query = new StringBuffer(
+                        StringBuilder query = new StringBuilder(
                                 "SELECT COUNT(*) FROM people");
                         if (!filters.isEmpty()) {
                             query.append(QueryBuilder

server/src/main/java/com/vaadin/server/ComponentSizeValidator.java

@@ -124,7 +124,7 @@ public class ComponentSizeValidator implements Serializable {
     private static void printServerError(String msg,
             Deque<ComponentInfo> attributes, boolean widthError,
             PrintStream errorStream) {
-        StringBuffer err = new StringBuffer();
+        StringBuilder err = new StringBuilder();
         err.append("Vaadin DEBUG\n");
 
         StringBuilder indent = new StringBuilder();
@@ -369,7 +369,7 @@ public class ComponentSizeValidator implements Serializable {
     }
 
     private static void showComponent(Component component, String attribute,
-            StringBuffer err, StringBuilder indent, boolean widthError) {
+            StringBuilder err, StringBuilder indent, boolean widthError) {
 
         FileLocation createLoc = creationLocations.get(component);
 

server/src/main/java/com/vaadin/server/communication/ResourceWriter.java

@@ -79,7 +79,7 @@ public class ResourceWriter implements Serializable {
 
                 writer.write((resourceIndex++ > 0 ? ", " : "") + "\"" + resource
                         + "\" : ");
-                final StringBuffer layout = new StringBuffer();
+                final StringBuilder layout = new StringBuilder();
 
                 try (InputStreamReader r = new InputStreamReader(is,
                         StandardCharsets.UTF_8)) {

uitest/src/main/java/com/vaadin/tests/TestForContainerFilterable.java

@@ -100,7 +100,7 @@ public class TestForContainerFilterable extends CustomComponent {
 
     private String randomWord() {
         int len = (int) (Math.random() * 4);
-        final StringBuffer buf = new StringBuffer();
+        final StringBuilder buf = new StringBuilder();
         while (len-- >= 0) {
             buf.append(parts[(int) (Math.random() * parts.length)]);
         }

uitest/src/main/java/com/vaadin/tests/TestForStyledUpload.java

@@ -156,7 +156,7 @@ public class TestForStyledUpload extends LegacyApplication
     }
 
     public void readState() {
-        final StringBuffer sb = new StringBuffer();
+        final StringBuilder sb = new StringBuilder();
 
         if (up.isUploading()) {
             sb.append("Uploading...");
@@ -293,7 +293,7 @@ public class TestForStyledUpload extends LegacyApplication
 
     private void refreshMemUsage() {
         // memoryStatus.setValue("Not available in Java 1.4");
-        StringBuffer mem = new StringBuffer();
+        StringBuilder mem = new StringBuilder();
         MemoryMXBean mmBean = ManagementFactory.getMemoryMXBean();
         mem.append("Heap (M):");
         mem.append(mmBean.getHeapMemoryUsage().getUsed() / 1048576);

uitest/src/main/java/com/vaadin/tests/TestForUpload.java

@@ -273,7 +273,7 @@ public class TestForUpload extends CustomComponent
     }
 
     public void readState() {
-        final StringBuffer sb = new StringBuffer();
+        final StringBuilder sb = new StringBuilder();
 
         if (up.isUploading()) {
             sb.append("Uploading...");
@@ -442,7 +442,7 @@ public class TestForUpload extends CustomComponent
     private void refreshMemUsage() {
         memoryStatus.setValue("Not available in Java 1.4");
 
-        StringBuffer mem = new StringBuffer();
+        StringBuilder mem = new StringBuilder();
         MemoryMXBean mmBean = ManagementFactory.getMemoryMXBean();
         mem.append("Heap (M):");
         mem.append(mmBean.getHeapMemoryUsage().getUsed() / 1048576);

uitest/src/main/java/com/vaadin/tests/TestSizeableIncomponents.java

@@ -235,7 +235,7 @@ public class TestSizeableIncomponents extends LegacyApplication {
         }
 
         public String getTestableName() {
-            StringBuffer sb = new StringBuffer();
+            StringBuilder sb = new StringBuilder();
             sb.append(classToTest.getName().replaceAll("com.vaadin.ui.", ""));
             sb.append('[');
             for (Iterator<Configuration> i = configurations.iterator(); i

uitest/src/main/java/com/vaadin/tests/components/table/HiddenColumnsExpandRatios.java

@@ -53,7 +53,7 @@ public class HiddenColumnsExpandRatios extends TestBase {
 
     private String genValue() {
         Random rnd = new Random();
-        StringBuffer str = new StringBuffer();
+        StringBuilder str = new StringBuilder();
         String[] strings = { "foo", "bar", "baz" };
         for (int i = 0; i < 5; i++) {
             str.append(strings[Math.abs(rnd.nextInt() % strings.length)])

uitest/src/main/java/com/vaadin/tests/components/tabsheet/TabSheetIndexOperations.java

@@ -38,7 +38,7 @@ public class TabSheetIndexOperations extends TestBase {
                     @Override
                     public void buttonClick(ClickEvent event) {
                         Tab tab = tabs.getTab(2);
-                        tab.setCaption(new StringBuffer(tab.getCaption())
+                        tab.setCaption(new StringBuilder(tab.getCaption())
                                 .reverse().toString());
                     }
                 });

uitest/src/main/java/com/vaadin/tests/util/LogPrintWriter.java

@@ -9,7 +9,7 @@ import java.io.Writer;
  */
 public class LogPrintWriter extends PrintWriter {
 
-    private final StringBuffer result = new StringBuffer(256);
+    private final StringBuilder result = new StringBuilder(256);
 
     public LogPrintWriter(Writer out) {
         super(out);