1 package JavaSyntaxHighterDemo;
2
3 import java.io.BufferedReader;
4 import java.io.File;
5 import java.io.FileInputStream;
6 import java.io.InputStreamReader;
7 import java.util.Arrays;
8 import java.util.HashSet;
9 import java.util.Set;
10
11 /**
12 * @author Kevin Tse
13 * @version 0.1
14 */
15 public class JavaSyntaxHighlighter {
16
17 public static int STATE_TEXT = 1; // 普通文本
18 public static int STATE_DOUBLE_QUOTE = 2; // 双引号
19 public static int STATE_SINGLE_QUOTE = 3; // 单引号
20 public static int STATE_MULTI_LINE_COMMENT = 4; // 多行注释
21 public static int STATE_LINE_COMMENT = 5; // 单行注释
22
23 private int lineNumber; // 行号
24 private boolean enableLineNumber = true; // 开启行号标志
25
26 public boolean isEnableLineNumber() {
27 return enableLineNumber;
28 }
29
30 // line numbers are printed by default.
31 // but this behavior can be disabled by invoking this method and setting the
32 // flag to false
33 public void setEnableLineNumber(boolean enableLineNumber) {
34 this.enableLineNumber = enableLineNumber;
35 }
36
37 String[] literalArray = { "null", "true", "false" }; //字面常量
38 String[] keywordArray = { "abstract", "break", "case", "catch", "class",
39 "const", "continue", "default", "do", "else", "extends", "final",
40 "finally", "for", "goto", "if", "implements", "import",
41 "instanceof", "interface", "native", "new", "package", "private",
42 "protected", "public", "return", "static", "strictfp", "super",
43 "switch", "synchronized", "this", "throw", "throws", "transient",
44 "try", "volatile", "while" }; //关键词
45 String[] primitiveTypeArray = { "boolean", "char", "byte", "short", "int",
46 "long", "float", "double", "void" }; //原始数据类型
47
48 Set<String> literalSet = new HashSet<String>(Arrays.asList(literalArray));
49 Set<String> keywordSet = new HashSet<String>(Arrays.asList(keywordArray));
50 Set<String> primitiveTypeSet = new HashSet<String>(Arrays
51 .asList(primitiveTypeArray));
52
53 public String process(String src) {
54 int currentState = STATE_TEXT;
55 int identifierLength = 0;
56 int currentIndex = -1;
57 char currentChar = 0;
58 String identifier = "";
59 StringBuffer out = new StringBuffer();
60
61 while (++currentIndex != src.length() - 1) {
62 currentChar = src.charAt(currentIndex);
63 if (Character.isJavaIdentifierPart(currentChar)) {
64 out.append(currentChar);
65 ++identifierLength;
66 continue;
67 }
68 if (identifierLength > 0) {
69 identifier = out.substring(out.length() - identifierLength);
70 if (currentState == STATE_TEXT) {
71 if (literalSet.contains(identifier)) { // identifier is a
72 // literal
73 out.insert(out.length() - identifierLength,
74 "<div class=\"literalStyle\">");
75 out.append("</div>");
76 } else if (keywordSet.contains(identifier)) { // identifier
77 // is a
78 // keyword
79 out.insert(out.length() - identifierLength,
80 "<div class=\"keywordStyle\">");
81 out.append("</div>");
82 } else if (primitiveTypeSet.contains(identifier)) { // identifier
83 // is a
84 // primitive
85 // type
86 out.insert(out.length() - identifierLength,
87 "<div class=\"primitiveTypeStyle\">");
88 out.append("</div>");
89 } else if (identifier.equals(identifier.toUpperCase())
90 && !Character.isDigit(identifier.charAt(0))) { // identifier
91 // is
92 // a
93 // constant
94 out.insert(out.length() - identifierLength,
95 "<div class=\"constantStyle\">");
96 out.append("</div>");
97 } else if (Character.isUpperCase(identifier.charAt(0))) { // identifier
98 // is
99 // non-primitive
100 // type
101 out.insert(out.length() - identifierLength,
102 "<div class=\"nonPrimitiveTypeStyle\">");
103 out.append("</div>");
104 }
105 }
106 }
107
108 switch (currentChar) {
109 // because I handle the "greater than" and "less than" marks
110 // somewhere else, I comment them out here
111 // case ‘<‘:
112 // out.append("<");
113 // break;
114 // case ‘>‘:
115 // out.append(">");
116 // break;
117 case ‘\"‘:
118 out.append(‘\"‘);
119 if (currentState == STATE_TEXT) {
120 currentState = STATE_DOUBLE_QUOTE;
121 out.insert(out.length() - ("\"").length(),
122 "<div class=\"doubleQuoteStyle\">");
123 } else if (currentState == STATE_DOUBLE_QUOTE) {
124 currentState = STATE_TEXT;
125 out.append("</div>");
126 }
127 break;
128 case ‘\‘‘:
129 out.append("\‘");
130 if (currentState == STATE_TEXT) {
131 currentState = STATE_SINGLE_QUOTE;
132 out.insert(out.length() - ("\‘").length(),
133 "<div class=\"singleQuoteStyle\">");
134 } else if (currentState == STATE_SINGLE_QUOTE) {
135 currentState = STATE_TEXT;
136 out.append("</div>");
137 }
138 break;
139 case ‘\\‘:
140 out.append("\\");
141 if (currentState == STATE_DOUBLE_QUOTE
142 || currentState == STATE_SINGLE_QUOTE) {
143 // treat as a character escape sequence
144 out.append(src.charAt(++currentIndex));
145 }
146 break;
147 // if you want to translate tabs into spaces, uncomment the
148 // following lines
149 // case ‘\t‘:
150 // // replace tabs with tabsize number of spaces
151 // for (int i = 0; i < tabSize; i++)
152 // out.append(" ");
153 // break;
154 case ‘*‘:
155 out.append(‘*‘);
156 if (currentState == STATE_TEXT && currentIndex > 0
157 && src.charAt(currentIndex - 1) == ‘/‘) {
158 out.insert(out.length() - ("/*").length(),
159 "<div class=\"multiLineCommentStyle\">");
160 currentState = STATE_MULTI_LINE_COMMENT;
161 }
162 break;
163 case ‘/‘:
164 out.append("/");
165 if (currentState == STATE_TEXT && currentIndex > 0
166 && src.charAt(currentIndex - 1) == ‘/‘) {
167 out.insert(out.length() - ("//").length(),
168 "<div class=\"singleLineCommentStyle\">");
169 currentState = STATE_LINE_COMMENT;
170 } else if (currentState == STATE_MULTI_LINE_COMMENT) {
171 out.append("</div>");
172 currentState = STATE_TEXT;
173 }
174 break;
175 case ‘\r‘:
176 case ‘\n‘:
177 // end single line comments
178 if (currentState == STATE_LINE_COMMENT) {
179 out.insert(out.length() - 1, "</div>");
180 currentState = STATE_TEXT;
181 }
182 if (currentChar == ‘\r‘ && currentIndex < src.length() - 1) {
183 out.append("\r\n");
184 ++currentIndex;
185 } else
186 out.append(‘\n‘);
187
188 if (enableLineNumber)
189 out.append("<div class=\"lineNumberStyle\">"
190 + (++lineNumber) + ".</div>");
191 break;
192 case 0:
193 if (currentState == STATE_LINE_COMMENT
194 && currentIndex == (src.length() - 1))
195 out.append("</div>");
196 break;
197 default: // everything else
198 out.append(currentChar);
199 }
200 identifierLength = 0;
201 }
202 return out.toString();
203 }
204
205 // test the program by reading a Java file as a String and letting the
206 // program process the source code
207 public static void main(String args[]) throws Exception {
208 File file = new File(
209 "src/JavaSyntaxHighterDemo/JavaSyntaxHighlighter.java");
210 BufferedReader br = new BufferedReader(new InputStreamReader(
211 new FileInputStream(file), "UTF-8"));
212 StringBuffer sb = new StringBuffer();
213 String temp = null;
214 while ((temp = br.readLine()) != null) {
215 sb.append(temp).append(‘\n‘);
216 }
217 String src = sb.toString();
218 JavaSyntaxHighlighter jsh = new JavaSyntaxHighlighter();
219 System.out.println(jsh.process(src));
220 }
221
222 }
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时间： 2024-07-28 19:31:50