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32 package com.imagero.uio.buffer.fm;
33
34 import com.imagero.uio.buffer.MutableRAFBufferManager;
35 import com.imagero.uio.buffer.Buffer;
36 import com.imagero.uio.buffer.RAFBuffer;
37 import com.imagero.uio.io.IOutils;
38 import com.imagero.uio.Sys;
39
40 import java.io.File  ;
41 import java.io.IOException ;
42 import java.io.RandomAccessFile ;
43 import java.awt.event.ActionListener ;
44 import java.awt.event.ActionEvent ;
45
46
50 class FMBufferManager extends MutableRAFBufferManager {
51
52 File file;
53 ActionListener listener;
54 volatile boolean reading, writing;
55
56 public FMBufferManager(File file, ActionListener listener) throws IOException {
57 super(new RandomAccessFile (file, "rw"));
58 this.listener = listener;
59 this.file = file;
60 }
61
62 public FMBufferManager(RandomAccessFile raf) throws IOException {
63 super(raf);
64 }
65
66 protected Buffer createBuffer(RandomAccessFile raf, long offset, int dsLength) {
67 long maxLength = 0;
68 try {
69 maxLength = raf.length() - offset;
70 }
71 catch (IOException ex) {
72 ex.printStackTrace();
73 }
74 if (maxLength < 0) {
75 return new FMBuffer(raf, offset, 0);
76 }
77 return new FMBuffer(raf, offset, (int) Math.min(maxLength, dsLength));
78 }
79
80 boolean canClose() {
81 return !reading && !writing;
82 }
83
84 void _close() {
85 super.close();
86 listener = null;
87 file = null;
88 raf = null;
89 }
90
91 public void close() {
92 IOutils.closeStream(raf);
93 raf = null;
94 listener.actionPerformed(new ActionEvent (this, ActionEvent.ACTION_PERFORMED, OpenFileManager.CLOSE));
95 if(OpenFileManager.debug && file != null) {
96 Sys.out.print("\nclose: ");
97 Sys.out.println(file.getAbsolutePath());
98 }
99 }
100
101 private RandomAccessFile get() throws IOException {
102 if (file == null) {
103 throw new NullPointerException ("This stream cannot be reopened!");
104 }
105 boolean opened = false;
106 if (raf == null) {
107 raf = new RandomAccessFile (file, "rw");
108 listener.actionPerformed(new ActionEvent (this, ActionEvent.ACTION_PERFORMED, OpenFileManager.OPEN));
109 opened = true;
110 if(OpenFileManager.debug && file != null) {
111 Sys.out.print("\nopen: ");
112 Sys.out.println(file.getAbsolutePath());
113 }
114 }
115 if(!opened) {
116 listener.actionPerformed(new ActionEvent (this, ActionEvent.ACTION_PERFORMED, OpenFileManager.GET));
117 }
118 return raf;
119 }
120
121 class FMBuffer extends RAFBuffer {
122
123 public FMBuffer(RandomAccessFile ra, long offset, int length) {
124 super(ra, offset, length);
125 }
126
127 protected void readData() throws IOException {
128 reading = true;
129 try {
130 raf = get();
131 super.readData();
132 }
133 finally {
134 reading = false;
135 }
136 }
137
138 protected void writeData() throws IOException {
139 writing = true;
140 try {
141 raf = get();
142 super.writeData();
143 }
144 finally {
145 writing = false;
146 }
147 }
148 }
149 }
150 |
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