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1 package gnu.kawa.functions;
2 import gnu.text.*;
3 import java.text.*;
4 import java.io.Writer  ;
5 import java.io.CharArrayWriter ;
6 import gnu.mapping.*;
7 import kawa.standard.Scheme;
8 import gnu.lists.AbstractFormat;
9
10 public class ObjectFormat extends ReportFormat
11 {
12
15 int maxChars;
16 boolean readable;
17
18 private static ObjectFormat readableFormat;
19 private static ObjectFormat plainFormat;
20
21 public static ObjectFormat getInstance(boolean readable)
22 {
23 if (readable)
24 {
25 if (readableFormat == null)
26 readableFormat = new ObjectFormat(true);
27 return readableFormat;
28 }
29 else
30 {
31 if (plainFormat == null)
32 plainFormat = new ObjectFormat(false);
33 return plainFormat;
34 }
35 }
36
37 public ObjectFormat(boolean readable)
38 {
39 this.readable = readable;
40 maxChars = PARAM_UNSPECIFIED;
41 }
42
43 public ObjectFormat(boolean readable, int maxChars)
44 {
45 this.readable = readable;
46 this.maxChars = maxChars;
47 }
48
49 public int format(Object [] args, int start, Writer dst, FieldPosition fpos)
50 throws java.io.IOException
51 {
52 int maxChars = getParam(this.maxChars, -1, args, start);
53 if (this.maxChars == PARAM_FROM_LIST) start++;
54 return format(args, start, dst, maxChars, readable);
55 }
56
57 private static void print (Object obj, OutPort out,
58 boolean readable)
59 {
60 boolean saveReadable = out.printReadable;
61 AbstractFormat saveFormat = out.objectFormat;
62 try
63 {
64 out.printReadable = readable;
65 AbstractFormat format
66 = readable ? Scheme.writeFormat : Scheme.displayFormat;
67 out.objectFormat = format;
68 format.writeObject(obj, (gnu.lists.Consumer) out);
69 }
70 finally
71 {
72 out.printReadable = saveReadable;
73 out.objectFormat = saveFormat;
74 }
75 }
76
77
81 public static boolean format(Object arg, Writer dst,
82 int maxChars, boolean readable)
83 throws java.io.IOException
84 {
85 if (maxChars < 0 && dst instanceof OutPort)
86 {
87 print(arg, (OutPort) dst, readable);
88 return true;
89 }
90 else if (maxChars < 0 && dst instanceof CharArrayWriter )
91 {
92 OutPort oport = new OutPort(dst);
93 print(arg, oport, readable);
94 oport.close();
95 return true;
96 }
97 else
98 {
99 CharArrayWriter wr = new CharArrayWriter ();
100 OutPort oport = new OutPort(wr);
101 print(arg, oport, readable);
102 oport.close();
103 int len = wr.size();
104 if (maxChars < 0 || len <= maxChars)
105 {
106 wr.writeTo(dst);
107 return true;
108 }
109 else
110 {
111 dst.write(wr.toCharArray(), 0, maxChars);
112 return false;
113 }
114 }
115 }
116
117 public static int format(Object [] args, int start, Writer dst,
118 int maxChars, boolean readable)
119 throws java.io.IOException
120 {
121 Object arg;
122 if (start >= args.length)
123 {
124 arg = "#<missing format argument>";
125 start--;
126 readable = false;
127 maxChars = -1;
128 }
129 else
130 arg = args[start];
131 format(arg, dst, maxChars, readable);
132 return start + 1;
133 }
134
135 public Object parseObject(String text, java.text.ParsePosition status)
136 {
137 throw new RuntimeException ("ObjectFormat.parseObject - not implemented");
138 }
139 }
140 |
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