使用 Jython 从 Java 代码调用 Python 导致错误：ImportError: no module named nltk

Question

我正在使用 PythonInterpreter 的 jython 从 java 代码中调用 python 代码。 python代码只是标记句子：

import nltk
import pprint

tokenizer = None
tagger = None   

def tag(sentences):
    global tokenizer
    global tagger
    tagged = nltk.sent_tokenize(sentences.strip())
    tagged = [nltk.word_tokenize(sent) for sent in tagged]
    tagged = [nltk.pos_tag(sent) for sent in tagged]
    return tagged

def PrintToText(tagged):
    output_file = open('/Users/ha/NetBeansProjects/JythonNLTK/src/jythonnltk/output.txt', 'w')
    output_file.writelines( "%s\n" % item for item in tagged )
    output_file.close()  

def main():
    sentences = """What is the salary of Jamie"""  
    tagged = tag(sentences)
    PrintToText(tagged)
    pprint.pprint(tagged)

if __name__ == 'main':    
    main()

我收到了这个错误：

run:
Traceback (innermost last):
  (no code object) at line 0
  File "/Users/ha/NetBeansProjects/JythonNLTK/src/jythonnltk/Code.py", line 42
        output_file.writelines( "%s\n" % item for item in tagged )
                                              ^
SyntaxError: invalid syntax
BUILD SUCCESSFUL (total time: 1 second)

如果我在 python 项目中打开它但从 java 调用它会触发此错误，则此代码工作得很好。我该如何解决？

提前致谢

更新： 我已按照@User 的建议将行编辑为output_file.writelines( ["%s\n" % item for item in tagged] )，但我收到了另一条错误消息：

Traceback (innermost last):
  File "/Users/ha/NetBeansProjects/JythonNLTK/src/jythonnltk/Code.py", line 5, in ?
ImportError: no module named nltk
BUILD SUCCESSFUL (total time: 1 second)

Answer 1

现在编译时语法错误已解决，您会遇到运行时错误。 nltk 是什么？ nltk 在哪里？ ImportError 表示 nltk 不在您的导入路径中。

尝试编写一个简单的小程序并检查sys.path；您可能需要在导入之前附加 nltk 的位置。

### The import fails if nltk is not in the system path:
>>> import nltk
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named nltk

### Try inspecting the system path:
>>> import sys
>>> sys.path
['', '/usr/lib/site-python', '/usr/share/jython/Lib', '__classpath__', '__pyclasspath__/', '/usr/share/jython/Lib/site-packages']

### Try appending the location of nltk to the system path:
>>> sys.path.append("/path/to/nltk")

#### Now try the import again.