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1
5 package org.h2.store;
6
7 import java.sql.SQLException  ;
8
9 import org.h2.engine.Constants;
10 import org.h2.message.Message;
11
12 public class DataPageText extends DataPage {
13
14 public DataPageText(DataHandler handler, byte[] data) {
15 super(handler, data);
16 }
17
18 public void setInt(int pos, int x) {
19 for(int i=7;i>=0;i--, x>>>= 4) {
20 data[i] = (byte)Character.forDigit(x & 0xf, 16);
21 }
22 }
23
24 public void updateChecksum() {
25 if(CHECKSUM) {
26 int x = handler.getChecksum(data, 0, pos-2);
27 data[pos-2] = (byte)('a' + (((x^(x>>4)) & 0xf)));
28 }
29 }
30
31 public void check(int len) throws SQLException {
32 if(CHECKSUM) {
33 int x = handler.getChecksum(data, 0, len-2);
34 if(data[len-2] == (byte)('a' + (((x^(x>>4)) & 0xf)))) {
35 return;
36 }
37 handler.handleInvalidChecksum();
38 }
39 }
40
41 public int getFillerLength() {
42 return 2;
43 }
44
45 public void writeInt(int x) {
46 if(Constants.CHECK) {
47 checkCapacity(8);
48 }
49 for(int i=7;i>=0;i--, x>>>= 4) {
50 data[pos+i] = (byte)Character.forDigit(x & 0xf, 16);
51 }
52 pos+=8;
53 }
54
55 public int readInt() {
56 int x = 0;
57 if(data[pos]==' ') {
58 pos += 8;
59 return 0;
60 }
61 for(int i=8, c;i>0;i--) {
62 x <<= 4;
63 x |= (c = data[pos++]) >= 'a' ? (c - 'a'+10) : (c - '0');
64 }
65 return x;
66 }
67
68 public int getIntLen() {
69 return 8;
70 }
71
72 public int getLongLen(long x) {
73 return 16;
74 }
75
76 public int getStringLen(String s) {
77 int len = 2 + s.length() + 1;
78 for (int i = 0; i < s.length(); i++) {
79 char c = s.charAt(i);
80 switch (c) {
81 case '\b':
82 case '\n':
83 case '\r':
84 case '\t':
85 case '\f':
86 case '"':
87 case '\\':
88 len++;
89 break;
90 default:
91 int ch = (c & 0xffff);
92 if ((ch >= ' ') && (ch <= 0xff)) {
93 } else {
95 len += 5;
96 }
97 }
98 }
99 return len;
100 }
101
102 public String readString() {
103 StringBuffer buff = new StringBuffer (32);
104 if(Constants.CHECK && data[pos] != '"') {
105 throw Message.getInternalError("\" expected");
106 }
107 pos++;
108 while(true) {
109 char x = (char)(data[pos++] & 0xff);
110 if(x == '"') {
111 break;
112 } else if(x=='\\') {
113 x = (char)data[pos++];
114 switch(x) {
115 case 't':
116 buff.append('\t');
117 break;
118 case 'r':
119 buff.append('\r');
120 break;
121 case 'n':
122 buff.append('\n');
123 break;
124 case 'b':
125 buff.append('\b');
126 break;
127 case 'f':
128 buff.append('\f');
129 break;
130 case '"':
131 buff.append('"');
132 break;
133 case '\\':
134 buff.append('\\');
135 break;
136 case 'u': {
137 x = 0;
138 for(int i=3, c;i>=0;i--) {
139 x <<= 4;
140 x |= (c = data[pos++]) >= 'a' ? (c - 'a'+10) : (c - '0');
141 }
142 buff.append(x);
143 break;
144 }
145 default:
146 throw Message.getInternalError("unexpected "+x);
147 }
148 } else {
149 buff.append(x);
150 }
151 }
152 pos++;
153 return buff.toString();
154 }
155
156 public void writeString(String s) {
157 checkCapacity(s.length()*6+2);
158 data[pos++] = '\"';
159 for (int i = 0; i < s.length(); i++) {
160 char c = s.charAt(i);
161 switch (c) {
162 case '\t':
163 data[pos++] = '\\'; data[pos++] = 't';
164 break;
165 case '\r':
166 data[pos++] = '\\'; data[pos++] = 'r';
167 break;
168 case '\n':
169 data[pos++] = '\\'; data[pos++] = 'n';
170 break;
171 case '\b':
172 data[pos++] = '\\'; data[pos++] = 'b';
173 break;
174 case '\f':
175 data[pos++] = '\\'; data[pos++] = 'f';
176 break;
177 case '"':
178 data[pos++] = '\\'; data[pos++] = '\"';
179 break;
180 case '\\':
181 data[pos++] = '\\'; data[pos++] = '\\';
182 break;
183 default:
184 int ch = (c & 0xffff);
185 if ((ch >= ' ') && (ch <= 0xff)) {
186 data[pos++] = (byte)ch;
187 } else {
188 data[pos++] = '\\';
189 data[pos++] = 'u';
190 for(int j=3;j>=0;j--, ch>>>= 4) {
191 data[pos+j] = (byte)Character.forDigit(ch & 0xf, 16);
192 }
193 pos += 4;
194 }
195 }
196 }
197 data[pos++] = '\"';
198 data[pos++] = ' ';
199 }
200
201 public void fill(int len) {
202 if (pos > len) {
203 pos = len;
204 }
205 checkCapacity(len-pos);
206 while(pos < len) {
207 data[pos++] = ' ';
208 }
209 data[pos-1] = '\n';
210 }
211 }
212 |
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