Use chain of .append() methods instead of String concatenation

Change-Id: I80b73b653e97904605dc62484a7448f3bfbf721d

3 files changed, 8 insertions, 10 deletions

diff --git a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
index e68fbb5903..7d4de85cfe 100644
--- a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
+++ b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
@@ -217,7 +217,7 @@ public class ComponentSizeValidator implements Serializable {
             Component parent = component.getParent();
             String paintableId = component.getConnectorId();
 
-            clientJSON.append("\"id\":\"" + paintableId + "\"");
+            clientJSON.append("\"id\":\"").append(paintableId).append("\"");
 
             if (invalidHeight) {
                 Stack<ComponentInfo> attributes = null;
@@ -247,7 +247,7 @@ public class ComponentSizeValidator implements Serializable {
                     attributes = getHeightAttributes(component);
                 }
                 printServerError(msg, attributes, false, serverErrorStream);
-                clientJSON.append(",\"heightMsg\":\"" + msg + "\"");
+                clientJSON.append(",\"heightMsg\":\"").append(msg).append("\"");
             }
             if (invalidWidth) {
                 Stack<ComponentInfo> attributes = null;
@@ -275,7 +275,7 @@ public class ComponentSizeValidator implements Serializable {
                     msg = "A component with relative width needs a parent with defined width.";
                     attributes = getWidthAttributes(component);
                 }
-                clientJSON.append(",\"widthMsg\":\"" + msg + "\"");
+                clientJSON.append(",\"widthMsg\":\"").append(msg).append("\"");
                 printServerError(msg, attributes, true, serverErrorStream);
             }
             if (subErrors.size() > 0) {
@@ -402,8 +402,7 @@ public class ComponentSizeValidator implements Serializable {
         }
 
         if (createLoc != null) {
-            err.append(", created at (" + createLoc.file + ":"
-                    + createLoc.lineNumber + ")");
+            err.append(", created at (").append(createLoc.file).append(":").append(createLoc.lineNumber).append(")");
 
         }
 
@@ -411,8 +410,7 @@ public class ComponentSizeValidator implements Serializable {
             err.append(" (");
             err.append(attribute);
             if (sizeLoc != null) {
-                err.append(", set at (" + sizeLoc.file + ":"
-                        + sizeLoc.lineNumber + ")");
+                err.append(", set at (").append(sizeLoc.file).append(":").append(sizeLoc.lineNumber).append(")");
             }
 
             err.append(")");
diff --git a/server/src/main/java/com/vaadin/server/JsonPaintTarget.java b/server/src/main/java/com/vaadin/server/JsonPaintTarget.java
index 4463fd1ab5..9792673062 100644
--- a/server/src/main/java/com/vaadin/server/JsonPaintTarget.java
+++ b/server/src/main/java/com/vaadin/server/JsonPaintTarget.java
@@ -443,7 +443,7 @@ public class JsonPaintTarget implements PaintTarget {
                     "Parameters must be non-null strings");
         }
         final StringBuilder buf = new StringBuilder();
-        buf.append("\"" + name + "\":[");
+        buf.append("\"").append(name).append("\":[");
         for (int i = 0; i < values.length; i++) {
             if (i > 0) {
                 buf.append(",");
@@ -743,7 +743,7 @@ public class JsonPaintTarget implements PaintTarget {
         private boolean tagClosed = false;
 
         public JsonTag(String tagName) {
-            data.append("[\"" + tagName + "\"");
+            data.append("[\"").append(tagName).append("\"");
         }
 
         private void closeTag() {
diff --git a/server/src/main/java/com/vaadin/server/communication/PortletBootstrapHandler.java b/server/src/main/java/com/vaadin/server/communication/PortletBootstrapHandler.java
index 2b40b6caca..a75e6a810b 100644
--- a/server/src/main/java/com/vaadin/server/communication/PortletBootstrapHandler.java
+++ b/server/src/main/java/com/vaadin/server/communication/PortletBootstrapHandler.java
@@ -78,7 +78,7 @@ public class PortletBootstrapHandler extends BootstrapHandler {
                 && !portalTheme.equals(context.getThemeName())) {
             String portalThemeUri = getThemeUri(context, portalTheme);
             // XSS safe - originates from portal properties
-            builder.append("vaadin.loadTheme('" + portalThemeUri + "');");
+            builder.append("vaadin.loadTheme('").append(portalThemeUri).append("');");
         }
 
         super.appendMainScriptTagContents(context, builder);