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1 /* |
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2 * Copyright (c) 1994, 2016, Oracle and/or its affiliates. All rights reserved. |
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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4 * |
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5 * This code is free software; you can redistribute it and/or modify it |
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6 * under the terms of the GNU General Public License version 2 only, as |
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7 * published by the Free Software Foundation. Oracle designates this |
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8 * particular file as subject to the "Classpath" exception as provided |
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9 * by Oracle in the LICENSE file that accompanied this code. |
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10 * |
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11 * This code is distributed in the hope that it will be useful, but WITHOUT |
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12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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14 * version 2 for more details (a copy is included in the LICENSE file that |
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15 * accompanied this code). |
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16 * |
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17 * You should have received a copy of the GNU General Public License version |
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18 * 2 along with this work; if not, write to the Free Software Foundation, |
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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20 * |
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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22 * or visit www.oracle.com if you need additional information or have any |
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23 * questions. |
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24 */ |
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25 |
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26 package java.io; |
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27 |
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28 /** |
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29 * A data input stream lets an application read primitive Java data |
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30 * types from an underlying input stream in a machine-independent |
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31 * way. An application uses a data output stream to write data that |
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32 * can later be read by a data input stream. |
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33 * <p> |
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34 * DataInputStream is not necessarily safe for multithreaded access. |
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35 * Thread safety is optional and is the responsibility of users of |
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36 * methods in this class. |
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37 * |
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38 * @author Arthur van Hoff |
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39 * @see java.io.DataOutputStream |
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40 * @since 1.0 |
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41 */ |
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42 public |
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43 class DataInputStream extends FilterInputStream implements DataInput { |
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44 |
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45 /** |
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46 * Creates a DataInputStream that uses the specified |
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47 * underlying InputStream. |
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48 * |
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49 * @param in the specified input stream |
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50 */ |
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51 public DataInputStream(InputStream in) { |
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52 super(in); |
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53 } |
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54 |
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55 /** |
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56 * working arrays initialized on demand by readUTF |
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57 */ |
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58 private byte bytearr[] = new byte[80]; |
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59 private char chararr[] = new char[80]; |
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60 |
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61 /** |
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62 * Reads some number of bytes from the contained input stream and |
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63 * stores them into the buffer array <code>b</code>. The number of |
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64 * bytes actually read is returned as an integer. This method blocks |
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65 * until input data is available, end of file is detected, or an |
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66 * exception is thrown. |
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67 * |
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68 * <p>If <code>b</code> is null, a <code>NullPointerException</code> is |
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69 * thrown. If the length of <code>b</code> is zero, then no bytes are |
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70 * read and <code>0</code> is returned; otherwise, there is an attempt |
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71 * to read at least one byte. If no byte is available because the |
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72 * stream is at end of file, the value <code>-1</code> is returned; |
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73 * otherwise, at least one byte is read and stored into <code>b</code>. |
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74 * |
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75 * <p>The first byte read is stored into element <code>b[0]</code>, the |
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76 * next one into <code>b[1]</code>, and so on. The number of bytes read |
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77 * is, at most, equal to the length of <code>b</code>. Let <code>k</code> |
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78 * be the number of bytes actually read; these bytes will be stored in |
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79 * elements <code>b[0]</code> through <code>b[k-1]</code>, leaving |
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80 * elements <code>b[k]</code> through <code>b[b.length-1]</code> |
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81 * unaffected. |
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82 * |
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83 * <p>The <code>read(b)</code> method has the same effect as: |
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84 * <blockquote><pre> |
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85 * read(b, 0, b.length) |
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86 * </pre></blockquote> |
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87 * |
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88 * @param b the buffer into which the data is read. |
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89 * @return the total number of bytes read into the buffer, or |
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90 * <code>-1</code> if there is no more data because the end |
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91 * of the stream has been reached. |
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92 * @exception IOException if the first byte cannot be read for any reason |
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93 * other than end of file, the stream has been closed and the underlying |
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94 * input stream does not support reading after close, or another I/O |
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95 * error occurs. |
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96 * @see java.io.FilterInputStream#in |
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97 * @see java.io.InputStream#read(byte[], int, int) |
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98 */ |
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99 public final int read(byte b[]) throws IOException { |
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100 return in.read(b, 0, b.length); |
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101 } |
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102 |
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103 /** |
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104 * Reads up to <code>len</code> bytes of data from the contained |
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105 * input stream into an array of bytes. An attempt is made to read |
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106 * as many as <code>len</code> bytes, but a smaller number may be read, |
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107 * possibly zero. The number of bytes actually read is returned as an |
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108 * integer. |
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109 * |
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110 * <p> This method blocks until input data is available, end of file is |
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111 * detected, or an exception is thrown. |
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112 * |
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113 * <p> If <code>len</code> is zero, then no bytes are read and |
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114 * <code>0</code> is returned; otherwise, there is an attempt to read at |
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115 * least one byte. If no byte is available because the stream is at end of |
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116 * file, the value <code>-1</code> is returned; otherwise, at least one |
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117 * byte is read and stored into <code>b</code>. |
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118 * |
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119 * <p> The first byte read is stored into element <code>b[off]</code>, the |
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120 * next one into <code>b[off+1]</code>, and so on. The number of bytes read |
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121 * is, at most, equal to <code>len</code>. Let <i>k</i> be the number of |
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122 * bytes actually read; these bytes will be stored in elements |
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123 * <code>b[off]</code> through <code>b[off+</code><i>k</i><code>-1]</code>, |
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124 * leaving elements <code>b[off+</code><i>k</i><code>]</code> through |
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125 * <code>b[off+len-1]</code> unaffected. |
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126 * |
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127 * <p> In every case, elements <code>b[0]</code> through |
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128 * <code>b[off]</code> and elements <code>b[off+len]</code> through |
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129 * <code>b[b.length-1]</code> are unaffected. |
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130 * |
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131 * @param b the buffer into which the data is read. |
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132 * @param off the start offset in the destination array <code>b</code> |
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133 * @param len the maximum number of bytes read. |
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134 * @return the total number of bytes read into the buffer, or |
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135 * <code>-1</code> if there is no more data because the end |
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136 * of the stream has been reached. |
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137 * @exception NullPointerException If <code>b</code> is <code>null</code>. |
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138 * @exception IndexOutOfBoundsException If <code>off</code> is negative, |
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139 * <code>len</code> is negative, or <code>len</code> is greater than |
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140 * <code>b.length - off</code> |
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141 * @exception IOException if the first byte cannot be read for any reason |
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142 * other than end of file, the stream has been closed and the underlying |
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143 * input stream does not support reading after close, or another I/O |
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144 * error occurs. |
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145 * @see java.io.FilterInputStream#in |
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146 * @see java.io.InputStream#read(byte[], int, int) |
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147 */ |
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148 public final int read(byte b[], int off, int len) throws IOException { |
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149 return in.read(b, off, len); |
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150 } |
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151 |
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152 /** |
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153 * See the general contract of the {@code readFully} |
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154 * method of {@code DataInput}. |
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155 * <p> |
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156 * Bytes |
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157 * for this operation are read from the contained |
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158 * input stream. |
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159 * |
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160 * @param b the buffer into which the data is read. |
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161 * @throws NullPointerException if {@code b} is {@code null}. |
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162 * @throws EOFException if this input stream reaches the end before |
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163 * reading all the bytes. |
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164 * @throws IOException the stream has been closed and the contained |
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165 * input stream does not support reading after close, or |
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166 * another I/O error occurs. |
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167 * @see java.io.FilterInputStream#in |
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168 */ |
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169 public final void readFully(byte b[]) throws IOException { |
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170 readFully(b, 0, b.length); |
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171 } |
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172 |
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173 /** |
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174 * See the general contract of the {@code readFully} |
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175 * method of {@code DataInput}. |
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176 * <p> |
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177 * Bytes |
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178 * for this operation are read from the contained |
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179 * input stream. |
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180 * |
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181 * @param b the buffer into which the data is read. |
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182 * @param off the start offset in the data array {@code b}. |
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183 * @param len the number of bytes to read. |
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184 * @exception NullPointerException if {@code b} is {@code null}. |
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185 * @exception IndexOutOfBoundsException if {@code off} is negative, |
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186 * {@code len} is negative, or {@code len} is greater than |
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187 * {@code b.length - off}. |
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188 * @exception EOFException if this input stream reaches the end before |
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189 * reading all the bytes. |
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190 * @exception IOException the stream has been closed and the contained |
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191 * input stream does not support reading after close, or |
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192 * another I/O error occurs. |
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193 * @see java.io.FilterInputStream#in |
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194 */ |
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195 public final void readFully(byte b[], int off, int len) throws IOException { |
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196 if (len < 0) |
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197 throw new IndexOutOfBoundsException(); |
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198 int n = 0; |
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199 while (n < len) { |
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200 int count = in.read(b, off + n, len - n); |
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201 if (count < 0) |
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202 throw new EOFException(); |
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203 n += count; |
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204 } |
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205 } |
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206 |
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207 /** |
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208 * See the general contract of the <code>skipBytes</code> |
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209 * method of <code>DataInput</code>. |
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210 * <p> |
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211 * Bytes for this operation are read from the contained |
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212 * input stream. |
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213 * |
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214 * @param n the number of bytes to be skipped. |
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215 * @return the actual number of bytes skipped. |
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216 * @exception IOException if the contained input stream does not support |
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217 * seek, or the stream has been closed and |
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218 * the contained input stream does not support |
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219 * reading after close, or another I/O error occurs. |
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220 */ |
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221 public final int skipBytes(int n) throws IOException { |
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222 int total = 0; |
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223 int cur = 0; |
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224 |
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225 while ((total<n) && ((cur = (int) in.skip(n-total)) > 0)) { |
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226 total += cur; |
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227 } |
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228 |
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229 return total; |
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230 } |
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231 |
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232 /** |
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233 * See the general contract of the <code>readBoolean</code> |
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234 * method of <code>DataInput</code>. |
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235 * <p> |
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236 * Bytes for this operation are read from the contained |
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237 * input stream. |
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238 * |
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239 * @return the <code>boolean</code> value read. |
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240 * @exception EOFException if this input stream has reached the end. |
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241 * @exception IOException the stream has been closed and the contained |
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242 * input stream does not support reading after close, or |
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243 * another I/O error occurs. |
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244 * @see java.io.FilterInputStream#in |
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245 */ |
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246 public final boolean readBoolean() throws IOException { |
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247 int ch = in.read(); |
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248 if (ch < 0) |
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249 throw new EOFException(); |
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250 return (ch != 0); |
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251 } |
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252 |
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253 /** |
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254 * See the general contract of the <code>readByte</code> |
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255 * method of <code>DataInput</code>. |
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256 * <p> |
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257 * Bytes |
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258 * for this operation are read from the contained |
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259 * input stream. |
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260 * |
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261 * @return the next byte of this input stream as a signed 8-bit |
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262 * <code>byte</code>. |
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263 * @exception EOFException if this input stream has reached the end. |
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264 * @exception IOException the stream has been closed and the contained |
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265 * input stream does not support reading after close, or |
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266 * another I/O error occurs. |
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267 * @see java.io.FilterInputStream#in |
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268 */ |
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269 public final byte readByte() throws IOException { |
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270 int ch = in.read(); |
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271 if (ch < 0) |
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272 throw new EOFException(); |
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273 return (byte)(ch); |
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274 } |
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275 |
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276 /** |
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277 * See the general contract of the <code>readUnsignedByte</code> |
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278 * method of <code>DataInput</code>. |
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279 * <p> |
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280 * Bytes |
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281 * for this operation are read from the contained |
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282 * input stream. |
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283 * |
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284 * @return the next byte of this input stream, interpreted as an |
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285 * unsigned 8-bit number. |
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286 * @exception EOFException if this input stream has reached the end. |
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287 * @exception IOException the stream has been closed and the contained |
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288 * input stream does not support reading after close, or |
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289 * another I/O error occurs. |
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290 * @see java.io.FilterInputStream#in |
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291 */ |
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292 public final int readUnsignedByte() throws IOException { |
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293 int ch = in.read(); |
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294 if (ch < 0) |
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295 throw new EOFException(); |
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296 return ch; |
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297 } |
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298 |
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299 /** |
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300 * See the general contract of the <code>readShort</code> |
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301 * method of <code>DataInput</code>. |
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302 * <p> |
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303 * Bytes |
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304 * for this operation are read from the contained |
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305 * input stream. |
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306 * |
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307 * @return the next two bytes of this input stream, interpreted as a |
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308 * signed 16-bit number. |
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309 * @exception EOFException if this input stream reaches the end before |
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310 * reading two bytes. |
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311 * @exception IOException the stream has been closed and the contained |
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312 * input stream does not support reading after close, or |
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313 * another I/O error occurs. |
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314 * @see java.io.FilterInputStream#in |
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315 */ |
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316 public final short readShort() throws IOException { |
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317 int ch1 = in.read(); |
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318 int ch2 = in.read(); |
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319 if ((ch1 | ch2) < 0) |
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320 throw new EOFException(); |
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321 return (short)((ch1 << 8) + (ch2 << 0)); |
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322 } |
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323 |
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324 /** |
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325 * See the general contract of the <code>readUnsignedShort</code> |
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326 * method of <code>DataInput</code>. |
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327 * <p> |
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328 * Bytes |
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329 * for this operation are read from the contained |
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330 * input stream. |
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331 * |
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332 * @return the next two bytes of this input stream, interpreted as an |
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333 * unsigned 16-bit integer. |
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334 * @exception EOFException if this input stream reaches the end before |
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335 * reading two bytes. |
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336 * @exception IOException the stream has been closed and the contained |
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337 * input stream does not support reading after close, or |
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338 * another I/O error occurs. |
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339 * @see java.io.FilterInputStream#in |
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340 */ |
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341 public final int readUnsignedShort() throws IOException { |
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342 int ch1 = in.read(); |
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343 int ch2 = in.read(); |
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344 if ((ch1 | ch2) < 0) |
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345 throw new EOFException(); |
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346 return (ch1 << 8) + (ch2 << 0); |
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347 } |
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348 |
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349 /** |
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350 * See the general contract of the <code>readChar</code> |
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351 * method of <code>DataInput</code>. |
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352 * <p> |
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353 * Bytes |
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354 * for this operation are read from the contained |
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355 * input stream. |
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356 * |
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357 * @return the next two bytes of this input stream, interpreted as a |
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358 * <code>char</code>. |
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359 * @exception EOFException if this input stream reaches the end before |
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360 * reading two bytes. |
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361 * @exception IOException the stream has been closed and the contained |
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362 * input stream does not support reading after close, or |
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363 * another I/O error occurs. |
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364 * @see java.io.FilterInputStream#in |
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365 */ |
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366 public final char readChar() throws IOException { |
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367 int ch1 = in.read(); |
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368 int ch2 = in.read(); |
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369 if ((ch1 | ch2) < 0) |
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370 throw new EOFException(); |
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371 return (char)((ch1 << 8) + (ch2 << 0)); |
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372 } |
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373 |
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374 /** |
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375 * See the general contract of the <code>readInt</code> |
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376 * method of <code>DataInput</code>. |
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377 * <p> |
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378 * Bytes |
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379 * for this operation are read from the contained |
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380 * input stream. |
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381 * |
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382 * @return the next four bytes of this input stream, interpreted as an |
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383 * <code>int</code>. |
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384 * @exception EOFException if this input stream reaches the end before |
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385 * reading four bytes. |
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386 * @exception IOException the stream has been closed and the contained |
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387 * input stream does not support reading after close, or |
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388 * another I/O error occurs. |
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389 * @see java.io.FilterInputStream#in |
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390 */ |
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391 public final int readInt() throws IOException { |
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392 int ch1 = in.read(); |
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393 int ch2 = in.read(); |
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394 int ch3 = in.read(); |
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395 int ch4 = in.read(); |
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396 if ((ch1 | ch2 | ch3 | ch4) < 0) |
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397 throw new EOFException(); |
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398 return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0)); |
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399 } |
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400 |
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401 private byte readBuffer[] = new byte[8]; |
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402 |
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403 /** |
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404 * See the general contract of the <code>readLong</code> |
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405 * method of <code>DataInput</code>. |
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406 * <p> |
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407 * Bytes |
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408 * for this operation are read from the contained |
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409 * input stream. |
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410 * |
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411 * @return the next eight bytes of this input stream, interpreted as a |
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412 * <code>long</code>. |
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413 * @exception EOFException if this input stream reaches the end before |
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414 * reading eight bytes. |
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415 * @exception IOException the stream has been closed and the contained |
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416 * input stream does not support reading after close, or |
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417 * another I/O error occurs. |
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418 * @see java.io.FilterInputStream#in |
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419 */ |
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420 public final long readLong() throws IOException { |
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421 readFully(readBuffer, 0, 8); |
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422 return (((long)readBuffer[0] << 56) + |
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423 ((long)(readBuffer[1] & 255) << 48) + |
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424 ((long)(readBuffer[2] & 255) << 40) + |
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425 ((long)(readBuffer[3] & 255) << 32) + |
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426 ((long)(readBuffer[4] & 255) << 24) + |
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427 ((readBuffer[5] & 255) << 16) + |
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428 ((readBuffer[6] & 255) << 8) + |
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429 ((readBuffer[7] & 255) << 0)); |
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430 } |
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431 |
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432 /** |
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433 * See the general contract of the <code>readFloat</code> |
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434 * method of <code>DataInput</code>. |
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435 * <p> |
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436 * Bytes |
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437 * for this operation are read from the contained |
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438 * input stream. |
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439 * |
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440 * @return the next four bytes of this input stream, interpreted as a |
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441 * <code>float</code>. |
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442 * @exception EOFException if this input stream reaches the end before |
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443 * reading four bytes. |
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444 * @exception IOException the stream has been closed and the contained |
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445 * input stream does not support reading after close, or |
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446 * another I/O error occurs. |
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447 * @see java.io.DataInputStream#readInt() |
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448 * @see java.lang.Float#intBitsToFloat(int) |
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449 */ |
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450 public final float readFloat() throws IOException { |
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451 return Float.intBitsToFloat(readInt()); |
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452 } |
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453 |
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454 /** |
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455 * See the general contract of the <code>readDouble</code> |
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456 * method of <code>DataInput</code>. |
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457 * <p> |
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458 * Bytes |
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459 * for this operation are read from the contained |
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460 * input stream. |
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461 * |
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462 * @return the next eight bytes of this input stream, interpreted as a |
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463 * <code>double</code>. |
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464 * @exception EOFException if this input stream reaches the end before |
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465 * reading eight bytes. |
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466 * @exception IOException the stream has been closed and the contained |
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467 * input stream does not support reading after close, or |
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468 * another I/O error occurs. |
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469 * @see java.io.DataInputStream#readLong() |
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470 * @see java.lang.Double#longBitsToDouble(long) |
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471 */ |
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472 public final double readDouble() throws IOException { |
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473 return Double.longBitsToDouble(readLong()); |
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474 } |
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475 |
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476 private char lineBuffer[]; |
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477 |
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478 /** |
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479 * See the general contract of the <code>readLine</code> |
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480 * method of <code>DataInput</code>. |
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481 * <p> |
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482 * Bytes |
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483 * for this operation are read from the contained |
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484 * input stream. |
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485 * |
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486 * @deprecated This method does not properly convert bytes to characters. |
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487 * As of JDK 1.1, the preferred way to read lines of text is via the |
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488 * <code>BufferedReader.readLine()</code> method. Programs that use the |
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489 * <code>DataInputStream</code> class to read lines can be converted to use |
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490 * the <code>BufferedReader</code> class by replacing code of the form: |
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491 * <blockquote><pre> |
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492 * DataInputStream d = new DataInputStream(in); |
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493 * </pre></blockquote> |
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494 * with: |
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495 * <blockquote><pre> |
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496 * BufferedReader d |
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497 * = new BufferedReader(new InputStreamReader(in)); |
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498 * </pre></blockquote> |
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499 * |
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500 * @return the next line of text from this input stream. |
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501 * @exception IOException if an I/O error occurs. |
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502 * @see java.io.BufferedReader#readLine() |
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503 * @see java.io.FilterInputStream#in |
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504 */ |
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505 @Deprecated |
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506 public final String readLine() throws IOException { |
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507 char buf[] = lineBuffer; |
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508 |
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509 if (buf == null) { |
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510 buf = lineBuffer = new char[128]; |
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511 } |
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512 |
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513 int room = buf.length; |
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514 int offset = 0; |
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515 int c; |
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516 |
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517 loop: while (true) { |
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518 switch (c = in.read()) { |
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519 case -1: |
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520 case '\n': |
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521 break loop; |
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522 |
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523 case '\r': |
|
524 int c2 = in.read(); |
|
525 if ((c2 != '\n') && (c2 != -1)) { |
|
526 if (!(in instanceof PushbackInputStream)) { |
|
527 this.in = new PushbackInputStream(in); |
|
528 } |
|
529 ((PushbackInputStream)in).unread(c2); |
|
530 } |
|
531 break loop; |
|
532 |
|
533 default: |
|
534 if (--room < 0) { |
|
535 buf = new char[offset + 128]; |
|
536 room = buf.length - offset - 1; |
|
537 System.arraycopy(lineBuffer, 0, buf, 0, offset); |
|
538 lineBuffer = buf; |
|
539 } |
|
540 buf[offset++] = (char) c; |
|
541 break; |
|
542 } |
|
543 } |
|
544 if ((c == -1) && (offset == 0)) { |
|
545 return null; |
|
546 } |
|
547 return String.copyValueOf(buf, 0, offset); |
|
548 } |
|
549 |
|
550 /** |
|
551 * See the general contract of the <code>readUTF</code> |
|
552 * method of <code>DataInput</code>. |
|
553 * <p> |
|
554 * Bytes |
|
555 * for this operation are read from the contained |
|
556 * input stream. |
|
557 * |
|
558 * @return a Unicode string. |
|
559 * @exception EOFException if this input stream reaches the end before |
|
560 * reading all the bytes. |
|
561 * @exception IOException the stream has been closed and the contained |
|
562 * input stream does not support reading after close, or |
|
563 * another I/O error occurs. |
|
564 * @exception UTFDataFormatException if the bytes do not represent a valid |
|
565 * modified UTF-8 encoding of a string. |
|
566 * @see java.io.DataInputStream#readUTF(java.io.DataInput) |
|
567 */ |
|
568 public final String readUTF() throws IOException { |
|
569 return readUTF(this); |
|
570 } |
|
571 |
|
572 /** |
|
573 * Reads from the |
|
574 * stream <code>in</code> a representation |
|
575 * of a Unicode character string encoded in |
|
576 * <a href="DataInput.html#modified-utf-8">modified UTF-8</a> format; |
|
577 * this string of characters is then returned as a <code>String</code>. |
|
578 * The details of the modified UTF-8 representation |
|
579 * are exactly the same as for the <code>readUTF</code> |
|
580 * method of <code>DataInput</code>. |
|
581 * |
|
582 * @param in a data input stream. |
|
583 * @return a Unicode string. |
|
584 * @exception EOFException if the input stream reaches the end |
|
585 * before all the bytes. |
|
586 * @exception IOException the stream has been closed and the contained |
|
587 * input stream does not support reading after close, or |
|
588 * another I/O error occurs. |
|
589 * @exception UTFDataFormatException if the bytes do not represent a |
|
590 * valid modified UTF-8 encoding of a Unicode string. |
|
591 * @see java.io.DataInputStream#readUnsignedShort() |
|
592 */ |
|
593 public static final String readUTF(DataInput in) throws IOException { |
|
594 int utflen = in.readUnsignedShort(); |
|
595 byte[] bytearr = null; |
|
596 char[] chararr = null; |
|
597 if (in instanceof DataInputStream) { |
|
598 DataInputStream dis = (DataInputStream)in; |
|
599 if (dis.bytearr.length < utflen){ |
|
600 dis.bytearr = new byte[utflen*2]; |
|
601 dis.chararr = new char[utflen*2]; |
|
602 } |
|
603 chararr = dis.chararr; |
|
604 bytearr = dis.bytearr; |
|
605 } else { |
|
606 bytearr = new byte[utflen]; |
|
607 chararr = new char[utflen]; |
|
608 } |
|
609 |
|
610 int c, char2, char3; |
|
611 int count = 0; |
|
612 int chararr_count=0; |
|
613 |
|
614 in.readFully(bytearr, 0, utflen); |
|
615 |
|
616 while (count < utflen) { |
|
617 c = (int) bytearr[count] & 0xff; |
|
618 if (c > 127) break; |
|
619 count++; |
|
620 chararr[chararr_count++]=(char)c; |
|
621 } |
|
622 |
|
623 while (count < utflen) { |
|
624 c = (int) bytearr[count] & 0xff; |
|
625 switch (c >> 4) { |
|
626 case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: |
|
627 /* 0xxxxxxx*/ |
|
628 count++; |
|
629 chararr[chararr_count++]=(char)c; |
|
630 break; |
|
631 case 12: case 13: |
|
632 /* 110x xxxx 10xx xxxx*/ |
|
633 count += 2; |
|
634 if (count > utflen) |
|
635 throw new UTFDataFormatException( |
|
636 "malformed input: partial character at end"); |
|
637 char2 = (int) bytearr[count-1]; |
|
638 if ((char2 & 0xC0) != 0x80) |
|
639 throw new UTFDataFormatException( |
|
640 "malformed input around byte " + count); |
|
641 chararr[chararr_count++]=(char)(((c & 0x1F) << 6) | |
|
642 (char2 & 0x3F)); |
|
643 break; |
|
644 case 14: |
|
645 /* 1110 xxxx 10xx xxxx 10xx xxxx */ |
|
646 count += 3; |
|
647 if (count > utflen) |
|
648 throw new UTFDataFormatException( |
|
649 "malformed input: partial character at end"); |
|
650 char2 = (int) bytearr[count-2]; |
|
651 char3 = (int) bytearr[count-1]; |
|
652 if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80)) |
|
653 throw new UTFDataFormatException( |
|
654 "malformed input around byte " + (count-1)); |
|
655 chararr[chararr_count++]=(char)(((c & 0x0F) << 12) | |
|
656 ((char2 & 0x3F) << 6) | |
|
657 ((char3 & 0x3F) << 0)); |
|
658 break; |
|
659 default: |
|
660 /* 10xx xxxx, 1111 xxxx */ |
|
661 throw new UTFDataFormatException( |
|
662 "malformed input around byte " + count); |
|
663 } |
|
664 } |
|
665 // The number of chars produced may be less than utflen |
|
666 return new String(chararr, 0, chararr_count); |
|
667 } |
|
668 } |