如何在运行时配置java.library.path？

Question

在我的项目中，我需要在运行时配置java.library.path。 Java能给我这样的能力吗？

Answer 1

第一个选项是将java.library.path设置为不同的值

/**
 * Sets the java library path to the specified path
 *
 * @param path the new library path
 * @throws Exception
 */
public static void setLibraryPath(String path) throws Exception {
    System.setProperty("java.library.path", path);

    //set sys_paths to null
    final Field sysPathsField = ClassLoader.class.getDeclaredField("sys_paths");
    sysPathsField.setAccessible(true);
    sysPathsField.set(null, null);
}

第二个选项是将您的路径追加到java.library.path

/**
* Adds the specified path to the java library path
*
* @param pathToAdd the path to add
* @throws Exception
*/
public static void addLibraryPath(String pathToAdd) throws Exception{
    final Field usrPathsField = ClassLoader.class.getDeclaredField("usr_paths");
    usrPathsField.setAccessible(true);

    //get array of paths
    final String[] paths = (String[])usrPathsField.get(null);

    //check if the path to add is already present
    for(String path : paths) {
        if(path.equals(pathToAdd)) {
            return;
        }
    }

    //add the new path
    final String[] newPaths = Arrays.copyOf(paths, paths.length + 1);
    newPaths[newPaths.length-1] = pathToAdd;
    usrPathsField.set(null, newPaths);
}

取自fahd.blog