XPathCondition.java 文件源码

public boolean eval() throws BuildException {
    if (nullOrEmpty(fileName)) {
        throw new BuildException("No file set");
    }
    File file = new File(fileName);
    if (!file.exists() || file.isDirectory()) {
        throw new BuildException(
                "The specified file does not exist or is a directory");
    }
    if (nullOrEmpty(path)) {
        throw new BuildException("No XPath expression set");
    }
    XPath xpath = XPathFactory.newInstance().newXPath();
    InputSource inputSource = new InputSource(fileName);
    Boolean result = Boolean.FALSE;
    try {
        result = (Boolean) xpath.evaluate(path, inputSource,
                XPathConstants.BOOLEAN);
    } catch (XPathExpressionException e) {
        throw new BuildException("XPath expression fails", e);
    }
    return result.booleanValue();
}