17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.io;
27
28 /**
29 * This class implements a character buffer that can be used as a
30 * character-input stream.
31 *
32 * @author Herb Jellinek
33 * @since 1.1
34 */
35 public class CharArrayReader extends Reader {
36 /** The character buffer. */
37 protected char buf[];
38
39 /** The current buffer position. */
40 protected int pos;
41
42 /** The position of mark in buffer. */
43 protected int markedPos = 0;
44
45 /**
46 * The index of the end of this buffer. There is not valid
47 * data at or beyond this index.
48 */
49 protected int count;
50
51 /**
52 * Creates a CharArrayReader from the specified array of chars.
53 * @param buf Input buffer (not copied)
54 */
55 public CharArrayReader(char buf[]) {
56 this.buf = buf;
57 this.pos = 0;
58 this.count = buf.length;
59 }
60
61 /**
62 * Creates a CharArrayReader from the specified array of chars.
63 *
64 * <p> The resulting reader will start reading at the given
65 * {@code offset}. The total number of {@code char} values that can be
66 * read from this reader will be either {@code length} or
67 * {@code buf.length-offset}, whichever is smaller.
68 *
69 * @throws IllegalArgumentException
70 * If {@code offset} is negative or greater than
71 * {@code buf.length}, or if {@code length} is negative, or if
72 * the sum of these two values is negative.
73 *
74 * @param buf Input buffer (not copied)
75 * @param offset Offset of the first char to read
76 * @param length Number of chars to read
77 */
78 public CharArrayReader(char buf[], int offset, int length) {
79 if ((offset < 0) || (offset > buf.length) || (length < 0) ||
80 ((offset + length) < 0)) {
81 throw new IllegalArgumentException();
82 }
83 this.buf = buf;
84 this.pos = offset;
85 this.count = Math.min(offset + length, buf.length);
86 this.markedPos = offset;
87 }
88
89 /** Checks to make sure that the stream has not been closed */
90 private void ensureOpen() throws IOException {
91 if (buf == null)
92 throw new IOException("Stream closed");
93 }
94
95 /**
96 * Reads a single character.
97 *
98 * @exception IOException If an I/O error occurs
101 synchronized (lock) {
102 ensureOpen();
103 if (pos >= count)
104 return -1;
105 else
106 return buf[pos++];
107 }
108 }
109
110 /**
111 * Reads characters into a portion of an array.
112 * @param b Destination buffer
113 * @param off Offset at which to start storing characters
114 * @param len Maximum number of characters to read
115 * @return The actual number of characters read, or -1 if
116 * the end of the stream has been reached
117 *
118 * @exception IOException If an I/O error occurs
119 * @exception IndexOutOfBoundsException {@inheritDoc}
120 */
121 public int read(char b[], int off, int len) throws IOException {
122 synchronized (lock) {
123 ensureOpen();
124 if ((off < 0) || (off > b.length) || (len < 0) ||
125 ((off + len) > b.length) || ((off + len) < 0)) {
126 throw new IndexOutOfBoundsException();
127 } else if (len == 0) {
128 return 0;
129 }
130
131 if (pos >= count) {
132 return -1;
133 }
134
135 int avail = count - pos;
136 if (len > avail) {
137 len = avail;
138 }
139 if (len <= 0) {
140 return 0;
141 }
|
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.io;
27
28 /**
29 * This class implements a character buffer that can be used as a
30 * character-input stream.
31 *
32 * @author Herb Jellinek
33 * @since 1.1
34 */
35 public class CharArrayReader extends Reader {
36 /** The character buffer. */
37 protected char[] buf;
38
39 /** The current buffer position. */
40 protected int pos;
41
42 /** The position of mark in buffer. */
43 protected int markedPos = 0;
44
45 /**
46 * The index of the end of this buffer. There is not valid
47 * data at or beyond this index.
48 */
49 protected int count;
50
51 /**
52 * Creates a CharArrayReader from the specified array of chars.
53 * @param buf Input buffer (not copied)
54 */
55 public CharArrayReader(char[] buf) {
56 this.buf = buf;
57 this.pos = 0;
58 this.count = buf.length;
59 }
60
61 /**
62 * Creates a CharArrayReader from the specified array of chars.
63 *
64 * <p> The resulting reader will start reading at the given
65 * {@code offset}. The total number of {@code char} values that can be
66 * read from this reader will be either {@code length} or
67 * {@code buf.length-offset}, whichever is smaller.
68 *
69 * @throws IllegalArgumentException
70 * If {@code offset} is negative or greater than
71 * {@code buf.length}, or if {@code length} is negative, or if
72 * the sum of these two values is negative.
73 *
74 * @param buf Input buffer (not copied)
75 * @param offset Offset of the first char to read
76 * @param length Number of chars to read
77 */
78 public CharArrayReader(char[] buf, int offset, int length) {
79 if ((offset < 0) || (offset > buf.length) || (length < 0) ||
80 ((offset + length) < 0)) {
81 throw new IllegalArgumentException();
82 }
83 this.buf = buf;
84 this.pos = offset;
85 this.count = Math.min(offset + length, buf.length);
86 this.markedPos = offset;
87 }
88
89 /** Checks to make sure that the stream has not been closed */
90 private void ensureOpen() throws IOException {
91 if (buf == null)
92 throw new IOException("Stream closed");
93 }
94
95 /**
96 * Reads a single character.
97 *
98 * @exception IOException If an I/O error occurs
101 synchronized (lock) {
102 ensureOpen();
103 if (pos >= count)
104 return -1;
105 else
106 return buf[pos++];
107 }
108 }
109
110 /**
111 * Reads characters into a portion of an array.
112 * @param b Destination buffer
113 * @param off Offset at which to start storing characters
114 * @param len Maximum number of characters to read
115 * @return The actual number of characters read, or -1 if
116 * the end of the stream has been reached
117 *
118 * @exception IOException If an I/O error occurs
119 * @exception IndexOutOfBoundsException {@inheritDoc}
120 */
121 public int read(char[] b, int off, int len) throws IOException {
122 synchronized (lock) {
123 ensureOpen();
124 if ((off < 0) || (off > b.length) || (len < 0) ||
125 ((off + len) > b.length) || ((off + len) < 0)) {
126 throw new IndexOutOfBoundsException();
127 } else if (len == 0) {
128 return 0;
129 }
130
131 if (pos >= count) {
132 return -1;
133 }
134
135 int avail = count - pos;
136 if (len > avail) {
137 len = avail;
138 }
139 if (len <= 0) {
140 return 0;
141 }
|