1 /*
   2  * Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.jfr.internal.cmd;
  27 
  28 import java.io.PrintWriter;
  29 
  30 abstract class StructuredWriter {
  31     private final static String LINE_SEPARATOR = String.format("%n");
  32 
  33     private final PrintWriter out;
  34     private final StringBuilder builder = new StringBuilder(4000);
  35 
  36     private char[] indentionArray = new char[0];
  37     private int indent = 0;
  38     private int column;
  39 
  40     StructuredWriter(PrintWriter p) {
  41         out = p;
  42     }
  43 
  44     final protected int getColumn() {
  45         return column;
  46     }
  47 
  48     // Flush to print writer
  49     public final void flush() {
  50         out.print(builder.toString());
  51         builder.setLength(0);
  52     }
  53 
  54     final public void printIndent() {
  55         builder.append(indentionArray, 0, indent);
  56         column += indent;
  57     }
  58 
  59     final public void println() {
  60         builder.append(LINE_SEPARATOR);
  61         column = 0;
  62     }
  63 
  64     final public void print(String... texts) {
  65         for (String text : texts) {
  66             print(text);
  67         }
  68     }
  69 
  70     final public void printAsString(Object o) {
  71         print(String.valueOf(o));
  72     }
  73 
  74     final public void print(String text) {
  75         builder.append(text);
  76         column += text.length();
  77     }
  78 
  79     final public void print(char c) {
  80         builder.append(c);
  81         column++;
  82     }
  83 
  84     final public void print(int value) {
  85         print(String.valueOf(value));
  86     }
  87 
  88     final public void indent() {
  89         indent += 2;
  90         updateIndent();
  91     }
  92 
  93     final public void retract() {
  94         indent -= 2;
  95         updateIndent();
  96     }
  97 
  98     final public void println(String text) {
  99         print(text);
 100         println();
 101     }
 102 
 103     private void updateIndent() {
 104         if (indent > indentionArray.length) {
 105             indentionArray = new char[indent];
 106             for (int i = 0; i < indentionArray.length; i++) {
 107                 indentionArray[i] = ' ';
 108             }
 109         }
 110     }
 111 }