为什么filenotfound异常没有在我的日志中打印/触发[重复]

Question

这个问题在这里已有答案：

• how to compare two strings in java? 3回答

所以我有两个方法，其代码我将在下面提出。第一种方法调用第二种方法，第二种方法负责打开读取数据的文件并将其发送到dataoutputstream请求变量。

我的问题是，如果文件不存在于文件夹中，我无法打印任何堆栈跟踪，或者如果调用第二个方法，则无法打印有关异常的信息。

但是，如果我不注释第一个方法中的注释行（它做同样的事情）并且根本不调用第二个方法，我能够在我的日志文件中看到日志，堆栈跟踪和文件未找到异常。

任何人都可以建议为什么会这样吗？即使调用第二个方法，我也需要能够使用找不到文件的异常：

public void addBodySend(String metadata, File file, String pMode) throws Exception{           
    try{
        request = new DataOutputStream(httpConn.getOutputStream());
        String post_data = crlf+twoHyphens + boundary + crlf+"Content-Disposition: form-data; name=\"properties\""+crlf+crlf+metadata+crlf+twoHyphens+boundary+crlf;
        String fileName = file.getName();
        post_data = post_data + "Content-Disposition: form-data; name=\"file\"; filename=\"" + fileName + "\""+crlf+"Content-Type: application/octet-stream"+crlf+crlf;
        request.writeBytes(post_data);
        if(pMode == "LOCAL_DIR"){
            this.getLocalFile(file);
        }
        /*fileInputStream = new FileInputStream(file);
        bufferedInputStream = new BufferedInputStream(fileInputStream);
        byte[] buffer;
        buffer = new byte[1024];
        int bytesRead=0;
        while((bytesRead = bufferedInputStream.read(buffer)) != -1){
            request.write(buffer,0,bytesRead);
            request.flush();
        }
        request.writeBytes(crlf+twoHyphens + boundary + twoHyphens + crlf);
        request.flush();*/
    }catch(Exception ex){
        this.sendStatus = false;
        ex.printStackTrace();
        log.writeln("Error while sending post request",0);
        for (StackTraceElement ste : Thread.currentThread().getStackTrace()) {
            log.writeln(ste.toString(),0);
        }
    }finally{
        if(bufferedInputStream!=null){
            try{
            bufferedInputStream.close();
            }catch(Exception ex){
                log.writeln("Error closing bufferred input stream",0);
            }
        }  
        if(request!=null){
            try{
            request.close();
            }catch(Exception ex){
                log.writeln("Error closing post request",0);
            }
        }    
    }
}

public void getLocalFile(File file) {
    try{
        fileInputStream = new FileInputStream(file);
        bufferedInputStream = new BufferedInputStream(fileInputStream);
        byte[] buffer;
        buffer = new byte[1024];
        int bytesRead=0;
        while((bytesRead = bufferedInputStream.read(buffer)) != -1){
            request.write(buffer,0,bytesRead);
            request.flush();
        }
        request.writeBytes(crlf+twoHyphens + boundary + twoHyphens + crlf);
        request.flush();   
        this.sendStatus = true;        
    }catch(Exception ex){
        this.sendStatus = false;
        ex.printStackTrace();
        log.writeln("Error while sending binary body",0);
        for (StackTraceElement ste : Thread.currentThread().getStackTrace()) {
            log.writeln(ste.toString(),0);
        }
    }finally{
        if(bufferedInputStream!=null){
            try{
            bufferedInputStream.close();
            }catch(Exception ex){
                log.writeln("Error closing bufferred input stream",0);
            }
        }
    }
}

Answer 1

尝试改变你比较这些字符串pMode和"LOCAL_DIR"的方式。代替

if(pMode == "LOCAL_DIR"){
     this.getLocalFile(file);
}

做

if("LOCAL_DIR".equals(pMode)){
      this.getLocalFile(file);
}

希望有所帮助