Add string modification to TestString.java

eaglesky · eaglesky · commit 384858c4e6b4 · 2016-11-27T00:05:17.000-08:00
diff --git a/TestString.java b/TestString.java
@@ -47,13 +47,17 @@ private static void stringBuilderDemo() {
         }
         String result = sb2.toString();
         System.out.println(result);
+
+        sb2.setCharAt(2, 'l');
+        sb2.setCharAt(7, 'j');
+        System.out.println(sb2);
 	}
 
 	// StringBuilder is essentially a wrapper of char[],
 	// with some additional funtionalities including resizing the char array.
 	// If char array can do the job then we should just use char array
 	private static void modifyString(String str) {
-		char[] chars = str.toCharArray();
+		char[] chars = str.toCharArray(); //Returns a deep copy of the char array in the string
 		for (char c : chars) {
 			System.out.print(c);
 		}
@@ -63,7 +67,7 @@ private static void modifyString(String str) {
 				chars[i] = '#';
 			}
 		}
-		String modified = String.valueOf(chars);
+		String modified = String.valueOf(chars); //Create a new string with a deep copy of chars array
 		System.out.println("Modified: " + modified);
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -47,13 +47,17 @@ private static void stringBuilderDemo() {`
`47`	`47`	`}`
`48`	`48`	`String result = sb2.toString();`
`49`	`49`	`System.out.println(result);`
	`50`	`+`
	`51`	`+ sb2.setCharAt(2, 'l');`
	`52`	`+ sb2.setCharAt(7, 'j');`
	`53`	`+ System.out.println(sb2);`
`50`	`54`	`}`
`51`	`55`
`52`	`56`	`// StringBuilder is essentially a wrapper of char[],`
`53`	`57`	`// with some additional funtionalities including resizing the char array.`
`54`	`58`	`// If char array can do the job then we should just use char array`
`55`	`59`	`private static void modifyString(String str) {`
`56`		`- char[] chars = str.toCharArray();`
	`60`	`+ char[] chars = str.toCharArray(); //Returns a deep copy of the char array in the string`
`57`	`61`	`for (char c : chars) {`
`58`	`62`	`System.out.print(c);`
`59`	`63`	`}`
`@@ -63,7 +67,7 @@ private static void modifyString(String str) {`
`63`	`67`	`chars[i] = '#';`
`64`	`68`	`}`
`65`	`69`	`}`
`66`		`- String modified = String.valueOf(chars);`
	`70`	`+ String modified = String.valueOf(chars); //Create a new string with a deep copy of chars array`
`67`	`71`	`System.out.println("Modified: " + modified);`
`68`	`72`	`}`
`69`	`73`