1 /**
2 * 2007, Digitalis Informatica. All rights reserved. Distribuicao e Gestao de Informatica, Lda. Estrada de Paco de Arcos
3 * num.9 - Piso -1 2780-666 Paco de Arcos Telefone: (351) 21 4408990 Fax: (351) 21 4408999 http://www.digitalis.pt
4 */
5 package pt.digitalis.dif.utils;
6
7 import java.util.ArrayList;
8 import java.util.Iterator;
9 import java.util.List;
10 import java.util.Map;
11
12 import pt.digitalis.utils.common.StringUtils;
13
14 /**
15 * Helps to format an object for printing in human readable form
16 *
17 * @author Pedro Viegas <a href="mailto:pviegas@digitalis.pt">pviegas@digitalis.pt</a>
18 * @created Dec 7, 2007
19 */
20 public class ObjectFormatter {
21
22 /** The prefix to format the lines with */
23 final static private String PREFIX = " | ";
24
25 /** The prefix to format the lines with */
26 final static private String SEPARATOR = ": ";
27
28 /** The generated buffer to return. Will be built incrementally */
29 private StringBuffer buffer = new StringBuffer();
30
31 /** the dumpd object list to keep track (avoid circular dump and stack overflow) */
32 private List<Object> dumpedObjects = new ArrayList<Object>();
33
34 /**
35 * Adds an item to the buffer
36 *
37 * @param key
38 * the key that identifies the value
39 * @param value
40 * the value
41 * @return the updated instance (fluent interface)
42 */
43 public ObjectFormatter addItem(String key, Object value)
44 {
45 if (!dumpedObjects.contains(value)
46 || (value != null && value.getClass().getPackage().getName().startsWith("java.lang")))
47 {
48 String line = PREFIX + key + SEPARATOR;
49 line += toStringParser(value, line.length());
50
51 if (!"".equals(buffer))
52 buffer.append("\n");
53
54 buffer.append(line);
55 }
56
57 return this;
58 }
59
60 /**
61 * Adds an item to the buffer if the value is not null
62 *
63 * @param key
64 * the key that identifies the value
65 * @param value
66 * the value
67 * @return the updated instance (fluent interface)
68 */
69 public ObjectFormatter addItemIfNotNull(String key, Object value)
70 {
71 if (value != null)
72 addItem(key, value);
73
74 return this;
75 }
76
77 /**
78 * Formats an iterator in human readable form
79 *
80 * @param obj
81 * the list to convert
82 * @return the formatted list
83 */
84 private String formatIterator(Iterable<?> obj)
85 {
86 if (!dumpedObjects.contains(obj))
87 {
88 dumpedObjects.add(obj);
89
90 Iterator<?> iterator = ((Iterable<?>) obj).iterator();
91
92 if (!iterator.hasNext())
93 return "[]";
94 else
95 {
96 String temp = "[\n";
97 int pos = 1;
98
99 while (iterator.hasNext())
100 {
101 Object object = iterator.next();
102 String ident = " #" + StringUtils.fillStringLeft(Integer.toString(pos++), 2, " ") + " ";
103 temp += ident + toStringParserWithPrefix(object, ident.length(), " ") + "\n";
104 }
105
106 return temp + "]";
107 }
108 }
109 else
110 return "«see above»";
111 }
112
113 /**
114 * Formats a map in human readable form
115 *
116 * @param map
117 * the map to convert
118 * @return the formatted map
119 */
120 private String formatMap(Map<?, ?> map)
121 {
122 if (!dumpedObjects.contains(map))
123 {
124 dumpedObjects.add(map);
125
126 if (map.size() == 0)
127 return "[]";
128 else
129 {
130 String temp = "[\n";
131 int pos = 1;
132
133 for (Object key: map.keySet())
134 {
135 String ident = " " + StringUtils.fillStringLeft("#" + Integer.toString(pos++), 3, " ") + " " + key
136 + " = ";
137 Object value = map.get(key);
138 if (value instanceof String)
139 {
140 value = "\"" + value + "\"";
141 }
142
143 temp += ident + toStringParserWithPrefix(value, ident.length(), " ") + "\n";
144 }
145
146 return temp + "]";
147 }
148 }
149 else
150 return "«see above»";
151 }
152
153 /**
154 * @return the formatted object
155 */
156 public String getFormatedObject()
157 {
158 return buffer.toString();
159 }
160
161 /**
162 * Parses a string and tries to format it for including has a value in a line.
163 *
164 * @param obj
165 * the object to format
166 * @param prefixSize
167 * the size of the necessary prefix
168 * @return the formatted string
169 */
170 private String toStringParser(Object obj, int prefixSize)
171 {
172 return toStringParserWithPrefix(obj, prefixSize, PREFIX);
173 }
174
175 /**
176 * Parses a string and tries to format it for including has a value in a line.
177 *
178 * @param obj
179 * the object to format
180 * @param prefixSize
181 * the size of the necessary prefix
182 * @param prefix
183 * the prefix to use to pad the string
184 * @return the formatted string
185 */
186 private String toStringParserWithPrefix(Object obj, int prefixSize, String prefix)
187 {
188 if (obj == null)
189 return null;
190 else
191 {
192 String temp;
193
194 if (obj instanceof Map)
195 temp = formatMap((Map<?, ?>) obj);
196
197 else if (obj instanceof Iterable)
198 temp = formatIterator(((Iterable<?>) obj));
199
200 else
201 temp = obj.toString();
202
203 dumpedObjects.add(obj);
204
205 return temp.replace("\n", "\n" + StringUtils.fillString(prefix, prefixSize, " "));
206 }
207 }
208 }