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2    * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
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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).
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24   */
25  
26  package sun.tools.jstat;
27  
28  import java.util.*;
29  
30  /**
31   * A typesafe enumeration for describing data alignment semantics
32   *
33   * @author Brian Doherty
34   * @since 1.5
35   */
36  public abstract class Alignment {
37  
38      private static int nextOrdinal = 0;
39      private static HashMap<String, Alignment> map = new HashMap<String, Alignment>();
40      private static final String blanks = "                                                                                                                                                               ";
41      private final String name;
42      private final int value = nextOrdinal++;
43  
44      protected abstract String align(String s, int width);
45  
46      /**
47       * Alignment representing a Centered alignment
48       */
49      public static final Alignment CENTER = new Alignment("center") {
50          protected String align(String s, int width) {
51              int length = s.length();
52              if (length >= width) {
53                  return s;
54              }
55  
56              int pad = width - length;
57              int pad2 = pad / 2;
58              int padr = pad % 2;
59              if (pad2 == 0) {
60                // only 0 or 1 character to pad
61                return s + blanks.substring(0, padr);
62              } else {
63                // pad on both sides
64                return  blanks.substring(0, pad2) + s +
65                        blanks.substring(0, pad2 + padr);
66              }
67          }
68      };
69  
70      /**
71       * Alignment representing a Left alignment
72       */
73      public static final Alignment LEFT = new Alignment("left") {
74          protected String align(String s, int width) {
75              int length = s.length();
76              if (length >= width) {
77                  return s;
78              }
79              int pad = width - length;
80              return s+blanks.substring(0, pad);
81          }
82      };
83  
84      /**
85       * Alignment representing a Right alignment
86       */
87      public static final Alignment RIGHT = new Alignment("right") {
88          protected String align(String s, int width) {
89              int length = s.length();
90              if (length >= width) {
91                  return s;
92              }
93              int pad = width - length;
94              return blanks.substring(0, pad) + s;
95          }
96      };
97  
98      /**
99       * Maps a string value to its corresponding Alignment object.
100      *
101      * @param   s  an string to match against Alignment objects.
102      * @return     The Alignment object matching the given string.
103      */
104     public static Alignment toAlignment(String s) {
105         return map.get(s);
106     }
107 
108     /**
109      * Returns an enumeration of the keys for this enumerated type
110      *
111      * @return     Set of Key Words for this enumeration.
112      */
113     public static Set keySet() {
114         return map.keySet();
115     }
116 
117     public String toString() {
118         return name;
119     }
120 
121     private Alignment(String name) {
122         this.name = name;
123         map.put(name, this);
124     }
125 }