Java Process：另一个程序正在使用此文件，进程无法访问

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@Test
public void test() throws Exception {
    String fileName = "out.log";
    File file = new File(fileName);
    Process process = new ProcessBuilder(getCommands(fileName)).redirectOutput(file).start();
    if(process.isAlive()) {
        process.waitFor();
    }
    BufferedReader readStderr = new BufferedReader(new InputStreamReader(process.getErrorStream(), "gbk"));
    String line;
    while((line = readStderr.readLine()) != null) {
        System.err.println(line);
    }
    readStderr.close();
}

public List<String> getCommands(String fileName) {
    String os = System.getProperty("os.name");
    if (os.toLowerCase().startsWith("win")) {
        return Arrays.asList("cmd", "/c", "echo", "hello world", ">", fileName);
    } else {
        return Arrays.asList("/bin/sh", "-c", "echo", "hello world", ">", fileName);
    }
}

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JNIEXPORT jlong JNICALL
Java_java_lang_ProcessImpl_create(JNIEnv *env, jclass ignored,
                                  jstring cmd,
                                  jstring envBlock,
                                  jstring dir,
                                  jlongArray stdHandles,
                                  jboolean redirectErrorStream)
{
    jlong ret = 0;
    if (cmd != NULL && stdHandles != NULL) {
        const jchar *pcmd = (*env)->GetStringChars(env, cmd, NULL);
        if (pcmd != NULL) {
            const jchar *penvBlock = (envBlock != NULL)
                ? (*env)->GetStringChars(env, envBlock, NULL)
                : NULL;
            if (!(*env)->ExceptionCheck(env)) {
                const jchar *pdir = (dir != NULL)
                    ? (*env)->GetStringChars(env, dir, NULL)
                    : NULL;
                if (!(*env)->ExceptionCheck(env)) {
                    jlong *handles = (*env)->GetLongArrayElements(env, stdHandles, NULL);
                    if (handles != NULL) {
                        ret = processCreate(
                            env,
                            pcmd,
                            penvBlock,
                            pdir,
                            handles,
                            redirectErrorStream);
                        (*env)->ReleaseLongArrayElements(env, stdHandles, handles, 0);
                    }
                    if (pdir != NULL)
                        (*env)->ReleaseStringChars(env, dir, pdir);
                }
                if (penvBlock != NULL)
                    (*env)->ReleaseStringChars(env, envBlock, penvBlock);
            }
            (*env)->ReleaseStringChars(env, cmd, pcmd);
        }
    }
    return ret;
}

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redirectOutput(file)
//和
">", fileName