Bug 577873: Add nullable annotations to IndentUtil

Change-Id: I28cec968788c195038bb16f143426ae3736c7668
diff --git a/ltk/org.eclipse.statet.ltk.core/src/org/eclipse/statet/ecommons/text/IndentUtil.java b/ltk/org.eclipse.statet.ltk.core/src/org/eclipse/statet/ecommons/text/IndentUtil.java
index f48263f..2e99881 100644
--- a/ltk/org.eclipse.statet.ltk.core/src/org/eclipse/statet/ecommons/text/IndentUtil.java
+++ b/ltk/org.eclipse.statet.ltk.core/src/org/eclipse/statet/ecommons/text/IndentUtil.java
@@ -21,6 +21,8 @@
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.osgi.util.NLS;
 
+import org.eclipse.statet.jcommons.lang.NonNullByDefault;
+import org.eclipse.statet.jcommons.lang.Nullable;
 import org.eclipse.statet.jcommons.text.core.TextRegion;
 
 import org.eclipse.statet.ecommons.text.IIndentSettings.IndentationType;
@@ -29,6 +31,7 @@
 /**
  * Util to compute and edit line indentations
  */
+@NonNullByDefault
 public class IndentUtil {
 	
 	public static final int COLUMN_IDX= 0;
@@ -129,19 +132,27 @@
 	
 	public static abstract class IndentEditAction {
 		
-		private int indentColumn;
+		private final int indentColumn;
+		
 		
 		public IndentEditAction() {
+			this.indentColumn= 0;
 		}
+		
 		public IndentEditAction(final int indentColumn) {
 			this.indentColumn= indentColumn;
 		}
+		
+		
 		public int getIndentColumn(final int line, final int lineOffset)
 				throws BadLocationException {
 			return this.indentColumn;
 		}
-		public abstract void doEdit(int line, int lineOffset, int length, StringBuilder text)
+		
+		public abstract void doEdit(int line, int lineOffset, int length,
+				@Nullable StringBuilder text)
 				throws BadLocationException;
+		
 	}
 	
 	
@@ -205,14 +216,14 @@
 							tabStart= (indentation/IndentUtil.this.tabWidth) * IndentUtil.this.tabWidth;
 							tabEnd= tabStart + IndentUtil.this.tabWidth;
 							if (IndentUtil.this.tabAsDefault && (tabEnd <= indentColumn)) {
-								spaceCount= indentation-tabStart;
-								replacement.delete(replacement.length()-spaceCount, replacement.length());
+								spaceCount= indentation - tabStart;
+								replacement.delete(replacement.length() - spaceCount, replacement.length());
 								replacement.append('\t');
 								indentation= tabEnd;
 								changed= true;
 							}
 							else {
-								spaceCount= indentColumn-indentation;
+								spaceCount= indentColumn - indentation;
 								replacement.append(repeat(' ', spaceCount));
 								indentation+= spaceCount;
 								changed= true;
@@ -223,7 +234,7 @@
 						}
 					}
 					if (changed) {
-						action.doEdit(line, lineInfo.getOffset(), offset-lineInfo.getOffset(), replacement);
+						action.doEdit(line, lineInfo.getOffset(), offset - lineInfo.getOffset(), replacement);
 						continue ITER_LINES;
 					}
 				}
@@ -284,7 +295,7 @@
 					appendIndent(replacement, column, indentColumn);
 				}
 				
-				action.doEdit(line, lineInfo.getOffset(), offset-lineInfo.getOffset(), replacement);
+				action.doEdit(line, lineInfo.getOffset(), offset - lineInfo.getOffset(), replacement);
 				continue ITER_LINES;
 			}
 		}
@@ -305,7 +316,7 @@
 					break ITERATE_CHAR;
 				}
 			}
-			return IndentUtil.this.document.get(lineInfo.getOffset(), offset-lineInfo.getOffset());
+			return IndentUtil.this.document.get(lineInfo.getOffset(), offset - lineInfo.getOffset());
 		}
 		
 	}
@@ -326,9 +337,9 @@
 				replacement.setLength(0);
 				appendIndent(replacement, indentColumn);
 				if (current[COLUMN_IDX] >= 0) {
-					appendSpaces(replacement, current[COLUMN_IDX]-indentColumn);
+					appendSpaces(replacement, current[COLUMN_IDX] - indentColumn);
 				}
-				action.doEdit(line, lineOffset, current[OFFSET_IDX]-lineOffset, replacement);
+				action.doEdit(line, lineOffset, current[OFFSET_IDX] - lineOffset, replacement);
 				continue ITER_LINES;
 			}
 		}
@@ -346,7 +357,7 @@
 				final int[] current= getLineIndent(line, false);
 				replacement.setLength(0);
 				appendIndent(replacement, indentColumn);
-				action.doEdit(line, lineOffset, current[OFFSET_IDX]-lineOffset, replacement);
+				action.doEdit(line, lineOffset, current[OFFSET_IDX] - lineOffset, replacement);
 				continue ITER_LINES;
 			}
 			
@@ -873,7 +884,7 @@
 //			s.append('\t');
 //		}
 //		else {
-//			s.append(repeat(' ', fNumOfSpaces-(currentColumn % fNumOfSpaces)));
+//			s.append(repeat(' ', numOfSpaces - (currentColumn % fNumOfSpaces)));
 //		}
 //	}