StringBuffer

kunal-kushwaha · kunal-kushwaha · commit b1ad614a0b2d · 2023-07-30T13:34:17.000+01:00
diff --git a/lectures/21-StringBuffer/code/Main.java b/lectures/21-StringBuffer/code/Main.java
@@ -0,0 +1,54 @@
+import java.util.Random;
+import java.util.Arrays;
+import java.text.DecimalFormat;
+
+class Main {
+  public static void main(String[] args) {
+    // constructor 1
+    StringBuffer sb = new StringBuffer();
+    System.out.println(sb.capacity());
+
+    // constructor 2
+    StringBuffer sb2 = new StringBuffer("Kunal Kushwaha");
+
+    // constructor 3
+    StringBuffer sb3 = new StringBuffer(30);
+    System.out.println(sb3.capacity());
+
+
+    sb.append("WeMakeDevs");
+    sb.append(" is nice!");
+
+    // sb.insert(2, " Rahul ");
+
+    sb.replace(1, 5, "Kushwaha");
+
+    sb.delete(1, 5);
+
+    // sb.reverse();
+
+    String str = sb.toString();
+    System.out.println(str);
+
+    int n = 20;
+    String name = RandomString.generate(n);
+    System.out.println(name);
+
+    // remove whitespaces
+
+    String sentence = "Hi h   hjh  hjkso  siowi     w ";
+    System.out.println(sentence);
+
+    System.out.println(sentence.replaceAll("\\s", ""));
+
+    // split
+
+    String arr = "Kunal,Apoorv,Rahul,Snehal";
+    String[] names = arr.split(",");
+    System.out.println(Arrays.toString(names));
+
+    // rounding off
+    DecimalFormat df = new DecimalFormat("00.0000");
+    System.out.println(df.format(7.29));
+  }
+}
diff --git a/lectures/21-StringBuffer/code/RandomString.java b/lectures/21-StringBuffer/code/RandomString.java
@@ -0,0 +1,16 @@
+import java.util.Random;
+
+class RandomString {
+  static String generate(int size) {
+    StringBuffer sb = new StringBuffer(size);
+
+    Random random = new Random();
+
+    for (int i=0; i < size; i++) {
+      int randomChar = 97 + (int)(random.nextFloat() * 26);
+      sb.append((char)randomChar);
+    }
+
+    return sb.toString();
+  }
+}
diff --git a/lectures/21-StringBuffer/notes/StringBuffer.pdf b/lectures/21-StringBuffer/notes/StringBuffer.pdf
