jscover.mozilla.javascript.tools.idswitch.README Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of rhino Show documentation
Show all versions of rhino Show documentation
Rhino is an open-source implementation of JavaScript written entirely in
Java. It is typically embedded into Java applications to provide
scripting to end users.
This Source Code Form is subject to the terms of the Mozilla Public
License, v. 2.0. If a copy of the MPL was not distributed with this
file, You can obtain one at http://mozilla.org/MPL/2.0/.
USING IDSWITCH GENERATOR TOOL
Usage:
java jscover.mozilla.javascript.tools.idswitch.Main
The main purpose of this utility is to generate Java code to map strings to some ids that can be used, for example, in a switch statement.
The utility scans the input file for lines with the following structure:
// #string_id_map#
...
// #generated#
...
// #/generated#
...
// #/string_id_map#
Then every line in is scanned for the pattern:
^[ \t]*Id_([0-9a-zA-Z_]+)[ \t]*=.*$
Each such patterns adds a mapping form string $1 to Id_\$ or if the line also contains the pattern //\s*#string=\s*([^#]+)\s*#, then it adds map of $1 in this pattern to Id_\$
After that lines in are replaced by a code block that sets variable "id" to Id_ if variable "s" equals (or value defined by //#string=...# construction in the line with Id_) or 0 otherwise.
If the new code for is identical to old one, the file is not touched otherwise is overwritten by the new code and a time stamp is appended after #generated#.
For example, if file x.java contains:
// #string_id_map#
private int getId(String s) {
int id;
// #generated# Initial version
// #/generated#
return id;
}
private static final int
Id_x = 1,
Id_y = 2,
Id_hello = 3, // #string = Hello, World! #
Id_symbols = 4, // #string=<<*Symbols*>>#
Id_nice = 5,
Id_for = 6,
Id_bar = 7;
// #/string_id_map#
....
private double getFieldValue(String s) {
// #string_id_map#
final int
Id_field1 = 1,
Id_field2 = 2,
Id_field3 = 3,
Id_one_more_field = 4; // #string = ONE%MORE%FIELD#
int id;
// #generated# Initial version
// #/generated#
// #/string_id_map#
switch (id) {
case Id_field1: return field1;
case Id_field2: return field2;
case Id_field3: return field3;
case Id_one_more_field: return one_more_field;
}
throw new RuntimeException("No such field");
}
then invocation
java jscover.mozilla.javascript.tools.idswitch.Main x.java
would replace that by a code fragment similar to:
// #string_id_map#
private int getId(String s) {
int id;
// #generated# Last update: 2001-05-25 18:00:24 GMT+02:00
L0: { id = 0; String X = null; int c;
L: switch (s.length()) {
case 1: c=s.charAt(0);
if (c=='x') { id=Id_x; break L0; }
else if (c=='y') { id=Id_y; break L0; }
break L;
case 3: c=s.charAt(0);
if (c=='b') { if (s.charAt(2)=='r' && s.charAt(1)=='a') {id=Id_bar; break L0;} }
else if (c=='f') { if (s.charAt(2)=='r' && s.charAt(1)=='o') {id=Id_for; break L0;} }
break L;
case 4: X="nice";id=Id_nice; break L;
case 13: c=s.charAt(0);
if (c=='<') { X="<<*Symbols*>>";id=Id_symbols; }
else if (c=='H') { X="Hello, World!";id=Id_hello; }
break L;
}
if (X!=null && X!=s && !X.equals(s)) id = 0;
}
// #/generated#
return id;
}
private static final int
Id_x = 1,
Id_y = 2,
Id_hello = 3, // #string = Hello, World! #
Id_symbols = 4, // #string=<<*Symbols*>>#
Id_nice = 5,
Id_for = 6,
Id_bar = 7;
// #/string_id_map#
....
private double getFieldValue(String s) {
// #string_id_map#
final int
Id_field1 = 1,
Id_field2 = 2,
Id_field3 = 3,
Id_one_more_field = 4; // #string = ONE%MORE%FIELD#
int id;
// #generated# Last update: 2001-05-25 16:48:50 GMT+02:00
L0: { id = 0; String X = null; int c;
int s_length = s.length();
if (s_length==6) {
c=s.charAt(5);
if (c=='1') { X="field1";id=Id_field1; }
else if (c=='2') { X="field2";id=Id_field2; }
else if (c=='3') { X="field3";id=Id_field3; }
}
else if (s_length==14) { X="ONE%MORE%FIELD";id=Id_one_more_field; }
if (X!=null && X!=s && !X.equals(s)) id = 0;
}
// #/generated#
// #/string_id_map#
switch (id) {
case Id_field1: return field1;
case Id_field2: return field2;
case Id_field3: return field3;
case Id_one_more_field: return one_more_field;
}
throw new RuntimeException("No such field");
}