main.java.coursier.paths.Jep Maven / Gradle / Ivy
package coursier.paths;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.*;
import java.util.regex.Pattern;
import java.util.stream.Stream;
public class Jep {
private static boolean existsInPath(String exec) {
// https://stackoverflow.com/questions/934191/how-to-check-existence-of-a-program-in-the-path/23539220#23539220
return Stream.of(System.getenv("PATH").split(Pattern.quote(File.pathSeparator)))
.map(Paths::get)
.anyMatch(path -> Files.exists(path.resolve(exec)));
}
// https://stackoverflow.com/questions/309424/how-do-i-read-convert-an-inputstream-into-a-string-in-java/309718#309718
private static String readFully(final InputStream is, final Charset charset, final int bufferSize) throws IOException {
final char[] buffer = new char[bufferSize];
final StringBuilder out = new StringBuilder();
try (Reader in = new InputStreamReader(is, charset)) {
for (;;) {
int rsz = in.read(buffer, 0, buffer.length);
if (rsz < 0)
break;
out.append(buffer, 0, rsz);
}
}
return out.toString();
}
public static class JepException extends Exception {
public JepException(String message) {
super(message);
}
}
private final static String locationLinePrefix = "Location: ";
public static File location() throws Exception {
String fromEnv = System.getenv("JEP_LOCATION");
if (fromEnv != null && !fromEnv.isEmpty())
return new File(fromEnv);
String fromProps = System.getProperty("jep.location");
if (fromProps != null && !fromProps.isEmpty())
return new File(fromProps);
String pip = "pip";
if (existsInPath("pip3"))
pip = "pip3";
ProcessBuilder b = new ProcessBuilder(pip, "show", "jep")
.redirectInput(ProcessBuilder.Redirect.PIPE)
.redirectOutput(ProcessBuilder.Redirect.PIPE)
.redirectError(ProcessBuilder.Redirect.INHERIT);
Process p = b.start();
p.getOutputStream().close(); // close sub-process stdin
String output = readFully(p.getInputStream(), Charset.defaultCharset(), 1024);
int retValue = p.waitFor();
if (retValue != 0) {
if (!output.isEmpty())
output = System.lineSeparator() + output;
throw new JepException("Error running " + pip + " show jep (return code: " + retValue + ")" + output);
}
Optional locationOpt = Stream.of(output.split(System.getProperty("line.separator")))
.filter(line -> line.startsWith(locationLinePrefix))
.findFirst();
if (!locationOpt.isPresent()) {
throw new JepException("No location found in " + pip + " show jep output:" + output);
}
File base = new File(locationOpt.get().substring(locationLinePrefix.length()));
return new File(base, "jep");
}
private final static String prefix = "jep-";
private final static String suffix = ".jar";
public static File jar(File jepDirectory) throws JepException {
File[] jars = jepDirectory.listFiles(f -> f.isFile() && f.getName().startsWith(prefix) && f.getName().endsWith(suffix));
if (jars == null || jars.length == 0)
return null;
else if (jars.length == 1)
return jars[0];
else {
StringBuilder b = new StringBuilder("Found too many jars in " + jepDirectory + ": ");
boolean isFirst = true;
for (File f: jars) {
if (isFirst)
isFirst = false;
else
b.append(", ");
b.append(f.getName());
}
throw new JepException(b.toString());
}
}
public static String version(File jepJar) throws JepException {
String name = jepJar.getName();
if (!name.startsWith(prefix))
throw new JepException("Invalid jep jar name: " + jepJar);
if (!name.endsWith(suffix))
throw new JepException("Invalid jep jar name: " + jepJar);
String version = name.substring(prefix.length(), name.length() - suffix.length());
return version;
}
public static String pythonHome() throws Exception {
String fromEnv = System.getenv("PYTHONHOME");
if (fromEnv != null && !fromEnv.isEmpty())
return fromEnv;
String fromProps = System.getProperty("python.home");
if (fromProps != null && !fromProps.isEmpty())
return fromProps;
String python = "python";
if (existsInPath("python3"))
python = "python3";
ProcessBuilder b = new ProcessBuilder(python, "-c", "import sys;print(sys.prefix)")
.redirectInput(ProcessBuilder.Redirect.PIPE)
.redirectOutput(ProcessBuilder.Redirect.PIPE)
.redirectError(ProcessBuilder.Redirect.INHERIT);
Process p = b.start();
p.getOutputStream().close(); // close sub-process stdin
String output = readFully(p.getInputStream(), Charset.defaultCharset(), 1024);
int retValue = p.waitFor();
if (retValue != 0) {
if (!output.isEmpty())
output = System.lineSeparator() + output;
throw new JepException("Error running " + python + " -c 'import sys; print(sys.prefix)' (return code: " + retValue + ")" + output);
}
return output.trim();
}
public static List> pythonProperties() throws Exception {
String jnaLibraryPath = new File(new File(pythonHome()), "lib").getAbsolutePath();
ArrayList> list = new ArrayList<>();
list.add(new AbstractMap.SimpleEntry<>("jna.library.path", jnaLibraryPath));
list.add(new AbstractMap.SimpleEntry<>("jna.nosys", "false"));
return list;
}
}