我收到了decrypt.jar
和encrypt.jar
文件,用于在传输之前准备文件。
当我启动终端并输入:
/usr/bin/java -jar /path/to/jar/decrypt.jar
我得到了输出:
No input file specified
哪个好!罐子工作。现在在我的代码中,当我使用execl()启动jar时,我将其作为输出:
Error: Could not find or load main class util.decrypt.jar
Decryptor exited with 0
请注意,这里的问题是java试图启动实际上是jar路径的类(路径是util / decrypt.jar,并将其作为类util.decrypt.jar执行)
我的代码:
bool decrypt_file(const std::string& file) {
int result;
int pipefd[2];
FILE *cmd_output;
char buf[1024];
int status;
result = pipe(pipefd);
if (result < 0) {
throw "pipe error!";
}
pid_t pid = fork(); /* Create a child process */
const std::string decryptJar = "util/decrypt.jar";
int ex;
if ( !fileExists(decryptJar) ) throw "File decryptor does not exist!";
switch (pid) {
case -1: /* Error */
#ifdef _DEBUG
std::cout<<"fork() failed!\n";
#endif
return false;
case 0: /* Child process */
dup2(pipefd[1], STDOUT_FILENO); /* Duplicate writing end to stdout */
close(pipefd[0]);
close(pipefd[1]);
//getJava() returns "/usr/bin/java"
ex = execl(Config::getInstance().getJava().c_str(), "-jar", decryptJar.c_str(), file.c_str(), NULL); /* Execute the program */
#ifdef _DEBUG
std::cout << "execl() failed! returned "<<ex<<", errno = "<<errno<<"\n"; /* execl doesn't return unless there's an error */
//todo if errno is 2, java was not found on the system, let the user know!
#endif
return false;
default: /* Parent process */
int status;
close(pipefd[1]); /* Close writing end of pipe */
cmd_output = fdopen(pipefd[0], "r");
#ifdef _DEBUG
if (fgets(buf, sizeof buf, cmd_output)) {
std::string str(buf);
std::cout<<"OUTPUT: "<<str<<"\n";
}
#endif
while (!WIFEXITED(status)) {
waitpid(pid, &status, 0); /* Wait for the process to complete */
}
#ifdef _DEBUG
std::cout << "Decryptor exited with " << WEXITSTATUS(status) << "\n";
#endif
return true;
}
}
jar中的清单是正确的(它是由eclipse生成的):
Manifest-Version: 1.0
Class-Path: .
Main-Class: com.{...}.Decryptor
添加:
尝试将路径更改为jar的绝对路径并没有解决问题。
const std::string decryptJar = workingDir() + "/util/decrypt.jar";
答案 0 :(得分:1)
<强>解决强>
我身边的愚蠢错误,按照惯例,第一个参数应该始终是可执行文件的路径。
所以
ex = execl(Config::getInstance().getJava().c_str(), "-jar", decryptJar.c_str(), file.c_str(), NULL); /* Execute the program */
应该是
ex = execl(Config::getInstance().getJava().c_str(), decryptJar.c_str(), "-jar", decryptJar.c_str(), file.c_str(), NULL); /* Execute the program */
发生的事情是java将“-jar”作为路径,因此我的命令实际上是
java pathToJar input
而不是
java -jar pathToJar input
修改:更正后的代码段:
bool decrypt_file(const std::string& javaPath, const std::string& file) {
int result, status;
int pipefd[2];
FILE *cmd_output;
char buf[1024];
int ex;
const std::string decryptJar = workingDir() + "/util/decrypt.jar";
result = pipe(pipefd);
if (result < 0) {
throw "pipe error!";
}
pid_t pid = fork(); /* Create a child process */
if ( !fileExists(decryptJar) ) throw "File decryptor does not exist!";
switch (pid) {
case -1: /* Error */
#ifdef _DEBUG
std::cout<<"fork() failed!\n";
#endif
return false;
case 0: /* Child process */
dup2(pipefd[1], STDOUT_FILENO); /* Duplicate writing end to stdout */
close(pipefd[0]);
close(pipefd[1]);
ex = execl(javaPath.c_str(), decryptJar.c_str(), "-jar", decryptJar.c_str(), file.c_str(), NULL); /* Execute the program */
#ifdef _DEBUG
std::cout << "execl() failed! returned "<<ex<<", errno = "<<errno<<"\n"; /* execl doesn't return unless there's an error */
#endif
if ( errno == 2 ) {
std::cout<<"JAVA NOT FOUND! Check if java is installed and/or if the path in the config file points to a correct java installation!\n\n";
}
return false;
default: /* Parent process */
close(pipefd[1]); /* Close writing end of pipe */
cmd_output = fdopen(pipefd[0], "r");
#ifdef _DEBUG
if (fgets(buf, sizeof buf, cmd_output)) {
std::string str(buf);
if ( str != "OK" )
std::cout<<"---DECRYPT OUTPUT: "<<str<<"\n";
}
#endif
while (!WIFEXITED(status)) {
waitpid(pid, &status, 0); /* Wait for the process to complete */
}
#ifdef _DEBUG
std::cout << "Decryptor exited with " << WEXITSTATUS(status) << "\n";
#endif
return true;
}
}