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1 package com.quadcap.sql;
2
3
40
41 import java.io.ByteArrayInputStream  ;
42 import java.io.IOException ;
43
44 import java.sql.SQLException ;
45
46 import com.quadcap.sql.io.ObjectInputStream;
47 import com.quadcap.sql.io.ObjectOutputStream;
48
49 import com.quadcap.sql.types.Type;
50 import com.quadcap.sql.types.Value;
51
52 import com.quadcap.sql.file.ByteArrayRandomAccess;
53 import com.quadcap.sql.file.Datafile;
54 import com.quadcap.sql.file.PageManager;
55 import com.quadcap.sql.file.RandomAccess;
56 import com.quadcap.sql.file.RandomAccessOutputStream;
57 import com.quadcap.sql.file.SubPageManager;
58
59 import com.quadcap.util.Debug;
60 import com.quadcap.util.Util;
61
62
67 public class LazyRow extends Row {
68 ByteArrayRandomAccess ra;
69 boolean[] dirty;
70
71 public LazyRow(int size) {
72 super(size);
73 this.dirty = new boolean[size + 1];
74 }
75
76 public void reset(RandomAccess rowBuf, Datafile db)
77 throws IOException , SQLException
78 {
79 resetDirty();
80 if (ra == null) {
81 ra = new ByteArrayRandomAccess((int)rowBuf.size());
82 }
83 ra.resize(rowBuf.size());
84 byte[] buf = ra.getBytes();
85 rowBuf.read(0, buf, 0, (int)rowBuf.size());
86 bulkLoad(db);
87 }
88
89 public void reset(byte[] buf, Datafile db)
90 throws IOException , SQLException
91 {
92 resetDirty();
93 if (ra == null) {
94 ra = new ByteArrayRandomAccess(buf);
95 } else {
96 ra.reset(buf, buf.length);
97 }
98 bulkLoad(db);
99 }
100
101 final void bulkLoad(Datafile db) throws SQLException {
102 try {
103 ByteArrayInputStream bi = new ByteArrayInputStream (getBytes());
104 ObjectInputStream oi = new ObjectInputStream(bi);
105 int rsize = oi.readInt();
106 if (rsize != size()) {
107 throw new RuntimeException ("Bad row size: " + rsize +
108 " vs tuple size: " + size());
109 }
110 this.blobCnt = oi.readInt();
111 for (int i = 1; i <= rsize; i++) {
112 Value vx = (Value)oi.readObject();
113 if (db != null) vx.setDatafile(db);
114 set(i, vx);
115 dirty[i] = false;
116 }
117 } catch (Throwable e) {
118 throw DbException.wrapThrowable(e);
119 }
120 }
121
122 public final void resetDirty() {
123 for (int i = 1; i <= size(); i++) {
124 dirty[i] = false;
125 }
126 }
127
128 final boolean isDirty() {
129 boolean d = false;
130 for (int i = 1; i < dirty.length && !d; i++) {
131 d = dirty[i];
132 }
133 return d;
134 }
135
136 public void set(int i, Value v) throws SQLException {
137 super.set(i, v);
138 dirty[i] = true;
139 }
140
141
142 final byte[] getBytes() throws IOException {
143 byte[] ret = ra.getBytes();
144 return ret;
145 }
146
147 final static byte[] writeRow(Session session, Tuple tuple, Row row)
148 throws IOException , SQLException
149 {
150 if (row instanceof LazyRow) {
151 LazyRow lrow = (LazyRow)row;
152 if (!lrow.isDirty()) {
153 byte[] buf = lrow.getBytes();
154 return buf;
155 }
156 }
157 ObjectOutputStream out = session.oos;
158 out.reset(null);
159 writeRow(tuple, row, out);
160 byte[] ret = out.toByteArray();
161 return ret;
162 }
163
164 final static String tn(Value v) throws SQLException {
166 StringBuffer sb = new StringBuffer (v.getType().toString());
167 sb.append(":");
168 sb.append(com.quadcap.sql.types.Value.tn(v));
169 sb.append("(=");
170 sb.append(String.valueOf(v));
171 sb.append(')');
172 return sb.toString();
173 }
174
176 final static void writeRow(Tuple tuple, Row row, ObjectOutputStream out)
177 throws IOException , SQLException
178 {
179 out.writeInt(row.size());
180 out.writeInt(row.blobCnt);
181 for (int i = 1; i <= row.size(); i++) {
182 Value vx = row.item(i);
183 if (tuple != null) {
184 Type t = tuple.getColumn(i).getType();
185 Value v1 = t.convert(vx);
186 vx = v1;
187 }
188 out.writeObject(vx);
189 }
190 }
191 }
192
193 |
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