< prev index next >

src/java.base/share/classes/java/nio/package-info.java

Print this page




  31  * <p> The central abstractions of the NIO APIs are: </p>
  32  *
  33  * <ul>
  34  *
  35  *   <li><p> <a href="#buffers"><i>Buffers</i></a>, which are containers for data;
  36  *   </p></li>
  37  *
  38  *   <li><p> <a
  39  *   href="charset/package-summary.html"><i>Charsets</i></a> and their
  40  *   associated <i>decoders</i> and <i>encoders</i>, <br> which
  41  *   translate between bytes and Unicode characters; </p></li>
  42  *
  43  *   <li><p> <a
  44  *   href="channels/package-summary.html"><i>Channels</i></a> of
  45  *   various types, which represent connections <br> to entities
  46  *   capable of performing I/O operations; and </p></li>
  47  *
  48  *   <li><p> <i>Selectors</i> and <i>selection keys</i>, which
  49  *   together with <br> <i>selectable channels</i> define a <a
  50  *   href="channels/package-summary.html#multiplex">multiplexed,
  51  *   non-blocking <br> I/O</a>&nbsp;facility.  </p></li>
  52  *
  53  *  </ul>
  54  *
  55  * <p> The {@code java.nio} package defines the buffer classes, which
  56  * are used throughout the NIO APIs.  The charset API is defined in
  57  * the {@link java.nio.charset} package, and the channel and selector
  58  * APIs are defined in the {@link java.nio.channels} package.  Each of
  59  * these subpackages has its own service-provider (SPI) subpackage,
  60  * the contents of which can be used to extend the platform's default
  61  * implementations or to construct alternative implementations.
  62  *
  63  * <a id="buffers"> </a>
  64  *
  65  * <blockquote><table class="borderless">
  66  *     <caption style="display:none">Description of the various buffers</caption>
  67  *   <tr><th style="text-align:left">Buffers</th>
  68  *       <th style="text-align:left">Description</th></tr>
  69  *   <tr><td style="vertical-align:top">{@link java.nio.Buffer}</td>



  70  *       <td>Position, limit, and capacity;
  71  *           <br>clear, flip, rewind, and mark/reset</td></tr>
  72  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.ByteBuffer}</td>
  73  *       <td>Get/put, compact, views; allocate,&nbsp;wrap</td></tr>
  74  *   <tr><td style="vertical-align:top">
  75  *       &nbsp;&nbsp;&nbsp;&nbsp;{@link java.nio.MappedByteBuffer}&nbsp;&nbsp;</td>

  76  *       <td>A byte buffer mapped to a file</td></tr>
  77  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.CharBuffer}</td>
  78  *       <td>Get/put, compact; allocate,&nbsp;wrap</td></tr>
  79  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.DoubleBuffer}</td>
  80  *       <td>&nbsp;&nbsp;&nbsp;&nbsp;'&nbsp;'</td></tr>
  81  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.FloatBuffer}</td>
  82  *       <td>&nbsp;&nbsp;&nbsp;&nbsp;'&nbsp;'</td></tr>
  83  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.IntBuffer}</td>
  84  *       <td>&nbsp;&nbsp;&nbsp;&nbsp;'&nbsp;'</td></tr>
  85  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.LongBuffer}</td>
  86  *       <td>&nbsp;&nbsp;&nbsp;&nbsp;'&nbsp;'</td></tr>
  87  *   <tr><td style="vertical-align:top">&nbsp;&nbsp;{@link java.nio.ShortBuffer}</td>
  88  *       <td>&nbsp;&nbsp;&nbsp;&nbsp;'&nbsp;'</td></tr>
  89  *   <tr><td style="vertical-align:top">{@link java.nio.ByteOrder}</td>
  90  *       <td>Typesafe enumeration for&nbsp;byte&nbsp;orders</td></tr>
  91  * </table></blockquote>







  92  *
  93  * <p> A <i>buffer</i> is a container for a fixed amount of data of a
  94  * specific primitive type.  In addition to its content a buffer has a
  95  * <i>position</i>, which is the index of the next element to be read
  96  * or written, and a <i>limit</i>, which is the index of the first
  97  * element that should not be read or written.  The base {@link
  98  * java.nio.Buffer} class defines these properties as well as methods
  99  * for <i>clearing</i>, <i>flipping</i>, and <i>rewinding</i>, for
 100  * <i>marking</i> the current position, and for <i>resetting</i> the
 101  * position to the previous mark.
 102  *
 103  * <p> There is a buffer class for each non-boolean primitive type.
 104  * Each class defines a family of <i>get</i> and <i>put</i> methods
 105  * for moving data out of and in to a buffer, methods for
 106  * <i>compacting</i>, <i>duplicating</i>, and <i>slicing</i> a buffer,
 107  * and static methods for <i>allocating</i> a new buffer as well as
 108  * for <i>wrapping</i> an existing array into a buffer.
 109  *
 110  * <p> Byte buffers are distinguished in that they can be used as the
 111  * sources and targets of I/O operations.  They also support several




  31  * <p> The central abstractions of the NIO APIs are: </p>
  32  *
  33  * <ul>
  34  *
  35  *   <li><p> <a href="#buffers"><i>Buffers</i></a>, which are containers for data;
  36  *   </p></li>
  37  *
  38  *   <li><p> <a
  39  *   href="charset/package-summary.html"><i>Charsets</i></a> and their
  40  *   associated <i>decoders</i> and <i>encoders</i>, <br> which
  41  *   translate between bytes and Unicode characters; </p></li>
  42  *
  43  *   <li><p> <a
  44  *   href="channels/package-summary.html"><i>Channels</i></a> of
  45  *   various types, which represent connections <br> to entities
  46  *   capable of performing I/O operations; and </p></li>
  47  *
  48  *   <li><p> <i>Selectors</i> and <i>selection keys</i>, which
  49  *   together with <br> <i>selectable channels</i> define a <a
  50  *   href="channels/package-summary.html#multiplex">multiplexed,
  51  *   non-blocking <br> I/O</a> facility.  </p></li>
  52  *
  53  *  </ul>
  54  *
  55  * <p> The {@code java.nio} package defines the buffer classes, which
  56  * are used throughout the NIO APIs.  The charset API is defined in
  57  * the {@link java.nio.charset} package, and the channel and selector
  58  * APIs are defined in the {@link java.nio.channels} package.  Each of
  59  * these subpackages has its own service-provider (SPI) subpackage,
  60  * the contents of which can be used to extend the platform's default
  61  * implementations or to construct alternative implementations.
  62  *
  63  * <a id="buffers"> </a>
  64  *
  65  * <table class="striped" style="margin-left:2em; text-align:left">
  66  *     <caption style="display:none">Description of the various buffers</caption>
  67  *   <thead>
  68  *   <tr><th scope="col">Buffers</th>
  69  *       <th scope="col">Description</th></tr>
  70  *   </thead>
  71  *   <tbody>
  72  *   <tr><th scope="row">{@link java.nio.Buffer}</th>
  73  *       <td>Position, limit, and capacity;
  74  *           clear, flip, rewind, and mark/reset</td></tr>
  75  *   <tr><th scope="row">
  76  *         <span style="padding-left:1em">{@link java.nio.ByteBuffer}</span></th>
  77  *       <td>Get/put, compact, views; allocate, wrap</td></tr>
  78  *   <tr><th scope="row">
  79  *         <span style="padding-left:2em">{@link java.nio.MappedByteBuffer}</span></th>
  80  *       <td>A byte buffer mapped to a file</td></tr>
  81  *   <tr><th scope="row">
  82  *         <span style="padding-left:1em">{@link java.nio.CharBuffer}</span></th>
  83  *       <td>Get/put, compact; allocate, wrap</td></tr>
  84  *   <tr><th scope="row">
  85  *         <span style="padding-left:1em">{@link java.nio.DoubleBuffer}</span></th>
  86  *       <td>Get/put, compact; allocate, wrap</td></tr>
  87  *   <tr><th scope="row">
  88  *         <span style="padding-left:1em">{@link java.nio.FloatBuffer}</span></th>
  89  *       <td>Get/put, compact; allocate, wrap</td></tr>
  90  *   <tr><th scope="row">
  91  *         <span style="padding-left:1em">{@link java.nio.IntBuffer}</span></th>
  92  *       <td>Get/put, compact; allocate, wrap</td></tr>
  93  *   <tr><th scope="row">
  94  *         <span style="padding-left:1em">{@link java.nio.LongBuffer}</span></th>
  95  *       <td>Get/put, compact; allocate, wrap</td></tr>
  96  *   <tr><th scope="row">
  97  *         <span style="padding-left:1em">{@link java.nio.ShortBuffer}</span></th>
  98  *       <td>Get/put, compact; allocate, wrap</td></tr>
  99  *   <tr><th scope="row">{@link java.nio.ByteOrder}</th>
 100  *       <td>Typesafe enumeration for byte orders</td></tr>
 101  * </tbody>
 102  * </table>
 103  *
 104  * <p> A <i>buffer</i> is a container for a fixed amount of data of a
 105  * specific primitive type.  In addition to its content a buffer has a
 106  * <i>position</i>, which is the index of the next element to be read
 107  * or written, and a <i>limit</i>, which is the index of the first
 108  * element that should not be read or written.  The base {@link
 109  * java.nio.Buffer} class defines these properties as well as methods
 110  * for <i>clearing</i>, <i>flipping</i>, and <i>rewinding</i>, for
 111  * <i>marking</i> the current position, and for <i>resetting</i> the
 112  * position to the previous mark.
 113  *
 114  * <p> There is a buffer class for each non-boolean primitive type.
 115  * Each class defines a family of <i>get</i> and <i>put</i> methods
 116  * for moving data out of and in to a buffer, methods for
 117  * <i>compacting</i>, <i>duplicating</i>, and <i>slicing</i> a buffer,
 118  * and static methods for <i>allocating</i> a new buffer as well as
 119  * for <i>wrapping</i> an existing array into a buffer.
 120  *
 121  * <p> Byte buffers are distinguished in that they can be used as the
 122  * sources and targets of I/O operations.  They also support several


< prev index next >