导入Jruby的Java类

Question

我正在尝试在Jruby中导入Java类

$ ls
bin src
$ ls bin/com/practice
Test.class
$ ls src/com/practice
Test.java
$ cat src/com/practice/Test.java
package com.practice;
public class Test {
    public static String foo(){
        return "Java!!";
    }
    public static void main(String args[]){
        System.out.println(Test.foo());
    }
}
$ jirb -Ibin
jruby-1.7.10 :001 > java_import 'com.pratice.Test'
NameError: cannot load Java class com.pratice.Test
    from org/jruby/javasupport/JavaClass.java:1250:in `for_name'
    from org/jruby/javasupport/JavaUtilities.java:34:in `get_proxy_class'
    from file:/Users/gaurish/.rvm/rubies/jruby-1.7.10/lib/jruby.jar!/jruby/java/core_ext/object.rb:26:in `java_import'
    from org/jruby/RubyArray.java:2409:in `map'
    from file:/Users/gaurish/.rvm/rubies/jruby-1.7.10/lib/jruby.jar!/jruby/java/core_ext/object.rb:22:in `java_import'
    from (irb):1:in `evaluate'
    from org/jruby/RubyKernel.java:1119:in `eval'
    from org/jruby/RubyKernel.java:1519:in `loop'
    from org/jruby/RubyKernel.java:1282:in `catch'
    from org/jruby/RubyKernel.java:1282:in `catch'
    from /Users/gaurish/.rvm/rubies/jruby-1.7.10/bin/jirb:13:in `(root)'

我在这里做错了什么？

Answer 1

您有许多问题：

1. 您在IRB中拼写错误的"练习"：java_import 'com.pratice.Test'
2. 您的班级实际上不在正确的软件包中。您需要将package com.practice;添加到Java代码。
3. 您需要向您的类路径添加" bin"，以便JVM可以找到类：$CLASSPATH << 'bin'

完全可以在IRB中运行它：

$CLASSPATH << 'bin'
com.practice.Test.foo
# => "Java!!"

编辑：我未能复制您的package行，这是我的错，而不是您的错。： - ）