37 |
|
|
38 |
package java.nio.charset; |
package java.nio.charset; |
39 |
|
|
40 |
class CoderResult |
import java.nio.BufferOverflowException; |
41 |
|
import java.nio.BufferUnderflowException; |
42 |
|
import java.util.HashMap; |
43 |
|
|
44 |
|
/** |
45 |
|
* @author Jesse Rosenstock |
46 |
|
* @since 1.4 |
47 |
|
*/ |
48 |
|
public class CoderResult |
49 |
{ |
{ |
50 |
boolean err; |
public static final CoderResult OVERFLOW |
51 |
|
= new CoderResult (TYPE_OVERFLOW, 0); |
52 |
boolean isError() |
public static final CoderResult UNDERFLOW |
53 |
{ |
= new CoderResult (TYPE_UNDERFLOW, 0); |
54 |
return err; |
|
55 |
} |
private static final int TYPE_MALFORMED = 0; |
56 |
|
private static final int TYPE_OVERFLOW = 1; |
57 |
boolean isMalformed() |
private static final int TYPE_UNDERFLOW = 2; |
58 |
{ |
private static final int TYPE_UNMAPPABLE = 3; |
59 |
return false; |
|
60 |
} |
private static final String[] names |
61 |
|
= { "MALFORMED", "OVERFLOW", "UNDERFLOW", "UNMAPPABLE" }; |
62 |
boolean isOverflow() |
|
63 |
{ |
private static final Cache malformedCache |
64 |
return false; |
= new Cache () |
65 |
} |
{ |
66 |
|
protected CoderResult make (int length) |
67 |
boolean isUnderflow() |
{ |
68 |
{ |
return new CoderResult (TYPE_MALFORMED, length); |
69 |
return false; |
} |
70 |
} |
}; |
71 |
|
|
72 |
boolean isUnmappable() |
private static final Cache unmappableCache |
73 |
{ |
= new Cache () |
74 |
return false; |
{ |
75 |
} |
protected CoderResult make (int length) |
76 |
|
{ |
77 |
int length() |
return new CoderResult (TYPE_UNMAPPABLE, length); |
78 |
{ |
} |
79 |
return 0; |
}; |
80 |
} |
|
81 |
|
private final int type; |
82 |
static CoderResult malformedForLength(int length) |
private final int length; |
83 |
{ |
|
84 |
return null; |
private CoderResult (int type, int length) |
85 |
} |
{ |
86 |
|
this.type = type; |
87 |
|
this.length = length; |
88 |
|
} |
89 |
|
|
90 |
|
public boolean isError () |
91 |
|
{ |
92 |
|
return length > 0; |
93 |
|
} |
94 |
|
|
95 |
|
public boolean isMalformed () |
96 |
|
{ |
97 |
|
return type == TYPE_MALFORMED; |
98 |
|
} |
99 |
|
|
100 |
|
public boolean isOverflow () |
101 |
|
{ |
102 |
|
return type == TYPE_OVERFLOW; |
103 |
|
} |
104 |
|
|
105 |
|
public boolean isUnderflow () |
106 |
|
{ |
107 |
|
return type == TYPE_UNDERFLOW; |
108 |
|
} |
109 |
|
|
110 |
|
public boolean isUnmappable () |
111 |
|
{ |
112 |
|
return type == TYPE_UNMAPPABLE; |
113 |
|
} |
114 |
|
|
115 |
|
public int length () |
116 |
|
{ |
117 |
|
if (length <= 0) |
118 |
|
throw new UnsupportedOperationException (); |
119 |
|
else |
120 |
|
return length; |
121 |
|
} |
122 |
|
|
123 |
|
public static CoderResult malformedForLength (int length) |
124 |
|
{ |
125 |
|
return malformedCache.get (length); |
126 |
|
} |
127 |
|
|
128 |
void throwException() |
public void throwException () |
129 |
throws CharacterCodingException |
throws CharacterCodingException |
130 |
{ |
{ |
131 |
throw new CharacterCodingException(); |
switch (type) |
132 |
} |
{ |
133 |
|
case TYPE_MALFORMED: |
134 |
|
throw new MalformedInputException (length); |
135 |
|
case TYPE_OVERFLOW: |
136 |
|
throw new BufferOverflowException (); |
137 |
|
case TYPE_UNDERFLOW: |
138 |
|
throw new BufferUnderflowException (); |
139 |
|
case TYPE_UNMAPPABLE: |
140 |
|
throw new UnmappableCharacterException (length); |
141 |
|
} |
142 |
|
} |
143 |
|
|
144 |
|
public String toString () |
145 |
|
{ |
146 |
|
String name = names[type]; |
147 |
|
return (length > 0) ? name + '[' + length + ']' : name; |
148 |
|
} |
149 |
|
|
150 |
|
public static CoderResult unmappableForLength (int length) |
151 |
|
{ |
152 |
|
return unmappableCache.get (length); |
153 |
|
} |
154 |
|
|
155 |
|
private abstract static class Cache |
156 |
|
{ |
157 |
|
private final HashMap cache; |
158 |
|
|
159 |
|
private Cache () |
160 |
|
{ |
161 |
|
// If we didn't synchronize on this, then cache would be initialized |
162 |
|
// without holding a lock. Undefined behavior would occur if the |
163 |
|
// first thread to call get(int) was not the same as the one that |
164 |
|
// called the constructor. |
165 |
|
synchronized (this) |
166 |
|
{ |
167 |
|
cache = new HashMap (); |
168 |
|
} |
169 |
|
} |
170 |
|
|
171 |
|
private synchronized CoderResult get (int length) |
172 |
|
{ |
173 |
|
if (length <= 0) |
174 |
|
throw new IllegalArgumentException ("Non-positive length"); |
175 |
|
|
176 |
|
Integer len = new Integer (length); |
177 |
|
CoderResult cr = null; |
178 |
|
Object o; |
179 |
|
if ((o = cache.get (len)) != null) |
180 |
|
cr = (CoderResult) ((WeakReference) o).get (); |
181 |
|
if (cr == null) |
182 |
|
{ |
183 |
|
cr = make (length); |
184 |
|
cache.put (len, cr); |
185 |
|
} |
186 |
|
|
187 |
public String toString() |
return cr; |
|
{ |
|
|
return "coder error"; |
|
188 |
} |
} |
189 |
|
|
190 |
static CoderResult unmappableForLength(int length) |
protected abstract CoderResult make (int length); |
191 |
{ |
} |
|
return null; |
|
|
} |
|
|
|
|
192 |
} |
} |