Java by API/java.lang/StringBuilder

new StringBuilder(int capacity)

 
public class Main {
  public static void main(String[] a) {
    StringBuilder builder1 = new StringBuilder();
    StringBuilder builder2 = new StringBuilder(0);
    StringBuilder builder3 = new StringBuilder(100);
    System.out.println(builder1.capacity());
    System.out.println(builder2.capacity());
    System.out.println(builder3.capacity());
  }
}
/*
16
0
100
*/

new StringBuilder(String str)

 

public class Main {
  public static void main(String[] args) {
    StringBuilder lipsum = new StringBuilder("Lorem ipsum dolor sit amet.");
    System.out.println("lipsum = " + lipsum.toString());
    lipsum.delete(0, 28);
    System.out.println("lipsum = " + lipsum.toString());
    lipsum.deleteCharAt(lipsum.length() - 1);
    System.out.println("lipsum = " + lipsum.toString());
  }
}

StringBuilder: append(char c)

 
/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.ru/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS""
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun"s Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun"s, and James Gosling"s,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */
/**
 * StringBuilderDemo: construct the same String three different ways.
 */
public class Main {
  public static void main(String[] argv) {
    String s1 = "Hello" + ", " + "World";
    System.out.println(s1);
    // Build a StringBuilder, and append some things to it.
    StringBuilder sb2 = new StringBuilder();
    sb2.append("Hello");
    sb2.append(",");
    sb2.append(" ");
    sb2.append("World");
    // Get the StringBuilder"s value as a String, and print it.
    String s2 = sb2.toString();
    System.out.println(s2);
    // Now do the above all over again, but in a more
    // concise (and typical "real-world" Java) fashion.
    StringBuilder sb3 = new StringBuilder().append("Hello").append(",")
        .append(" ").append("World");
    System.out.println(sb3.toString());
  }
}

StringBuilder: capacity()

 
public class Main {
  public static void main(String[] a) {
    StringBuilder builder1 = new StringBuilder();
    StringBuilder builder2 = new StringBuilder(0);
    StringBuilder builder3 = new StringBuilder(100);
    System.out.println(builder1.capacity());
    System.out.println(builder2.capacity());
    System.out.println(builder3.capacity());
  }
}
/*
16
0
100
*/

StringBuilder: delete(int start, int end)

 

public class Main {
  public static void main(String[] args) {
    StringBuilder lipsum = new StringBuilder("Lorem ipsum dolor sit amet.");
    System.out.println("lipsum = " + lipsum.toString());
    lipsum.delete(0, 28);
    System.out.println("lipsum = " + lipsum.toString());
    lipsum.deleteCharAt(lipsum.length() - 1);
    System.out.println("lipsum = " + lipsum.toString());
  }
}

StringBuilder: insert(int offset, String str)

 
public class Main {
  public static void main(String[] a) {
    StringBuilder builder = new StringBuilder("Line 1\n");
    builder.append("Line 3\n");
    String lineToInsert = "Line 2\n";
    
    builder.insert(0, lineToInsert);
    System.out.println(builder.toString());
  }
}
/*
Line 2
Line 1
Line 3
*/

StringBuilder: reverse()

 
/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
public class Main {
  public static void main(String[] args) {
    String palindrome = "Dot saw I was Tod";
    StringBuilder sb = new StringBuilder(palindrome);
    sb.reverse(); // reverse it
    System.out.println(sb);
  }
}

StringBuilder: toString()

 
public class Main {
  public static void main(String[] a) {
    StringBuilder builder = new StringBuilder("Line 1\n");
    builder.append("Line 3\n");
    String lineToInsert = "Line 2\n";
    
    builder.insert(0, lineToInsert);
    System.out.println(builder.toString());
  }
}
/*
Line 2
Line 1
Line 3
*/