Files
spring-tools/nodejs-packages/jvm-launch-utils/src/jvm-util.ts
2020-05-25 00:39:13 +02:00

301 lines
9.7 KiB
TypeScript

import * as FS from 'fs';
import * as Path from 'path';
import * as ChildProcess from 'child_process';
import { basename } from 'path';
'use strict';
export interface JVM {
/**
* 8 = Java 1.8.x, 9 = Java 9.x, etc
*/
getMajorVersion() : number
/**
* Path to the Java executable
*/
getJavaExecutable() : string
/**
* Path to the corresponding 'java home' for the executable.
*/
getJavaHome() : string
/**
* Detect whether this JVM is a JDK
*/
isJdk() : boolean
/**
* Find tools.jar for this JVM.
*
* Note that if the JVM is a JRE; or a Java 9 or above JDK;
* then this will return null.
*/
getToolsJar() : string | null
/**
* Launch an executable jar with this jvm.
* This autmatically adds tools.jar to the classpath if available.
* WARNING: For adding tools jar to work properly, the jar must be packaged
* using spring-boot-maven-plugin ZIP layout.
*/
jarLaunch(jar: string, vmargs?: string[], execFileOptions?: ChildProcess.ExecFileOptions) : ChildProcess.ChildProcess
mainClassLaunch(mainClass: string, classpath: string[], jvmArgs: string[], execFileOptions?: ChildProcess.ExecFileOptions): ChildProcess.ChildProcess
}
/**
* Find a JVM by looking in the JAVA_HOME and PATH environment variables.
*
* Optionally, a specific javaHome can be passed in. This shortcuts the
* search logic and uses that javaHome as is.
*
* The returned JVM may or may not be a JDK. Methods are provided to obtain corresponding
* toolsjar and to check whether the JVM is a JDK.
*/
export function findJvm(javaHome?: string) : Promise<JVM | null> {
try {
let javaExe = findJavaExe(javaHome);
if (javaExe) {
return getJavaInfo(javaExe).then(javaProps => new JVMImpl(
javaProps.get("java.home"),
javaExe,
getMajorVersion(javaProps)
));
}
return Promise.resolve(null);
} catch (e) {
return Promise.reject(e);
}
}
/**
* Like findJvm, but additionally, if the found JVM is not a JDK tries to
* find a companion JDK that may be installed alongside it.
*/
export function findJdk(javaHome?: string) : Promise<JVM | null> {
return findJvm(javaHome).then(jvm => {
if(!jvm) {
return null;
}
if (!jvm.isJdk()) {
console.log("found jvm is not a JDK");
//Try to find a 'sibling' JDK.
//Mainly for windows where it is common to have side-by-side install of a jre and jdk, instead of a
//nested jre install inside of a jdk.
//E.g.
//C:\ProgramFiles\Java\jdk1.8.0_161
//C:\ProgramFiles\Java\jre1.8.0_161
let javaExe = jvm.getJavaExecutable();
console.log("javaExe = ", javaExe);
// javaExe example: C:\ProgramFiles\Java\jre1.8.0_161\bin\java.exe
let jhome = jvm.getJavaHome();
console.log("jhome = ", jhome);
let basename : string = Path.basename(jhome);
console.log("basename = ", basename);
let altBasename : string = basename.replace("jre", "jdk");
console.log("altBasename = ", altBasename);
if (altBasename!==basename) {
let altHome = Path.join(Path.dirname(jhome), altBasename);
console.log("altHome = ", altHome);
if (FS.existsSync(altHome)) {
let altExe = Path.resolve(altHome, "bin", correctBinname("java"));
console.log("altExe = ", altExe);
return new JVMImpl(altHome, altExe, jvm.getMajorVersion());
}
}
}
return jvm;
});
}
/**
* Find a 'java' exe by looking in the JAVA_HOME and PATH environment variables.
* <p>
* Optionally, a specific javaHome can be passed in. This shortcuts the
* search logic and uses that javaHome as is, not looking anywhere else.
*/
function findJavaExe(javaHome?: string) : string | null {
//Try java home first
if (!javaHome) {
javaHome = process.env["JAVA_HOME"];
}
if (javaHome) {
//Resolve symlinks
javaHome = FS.realpathSync(javaHome);
}
let binName = correctBinname("java");
if (javaHome) {
let javaExe = Path.resolve(javaHome, "bin", binName);
if (FS.existsSync(javaExe)) {
return javaExe;
}
}
for (var searchPath of process.env['PATH'].split(Path.delimiter)) {
let javaExe = Path.resolve(searchPath, binName);
if (FS.existsSync(javaExe)) {
//Resolve symlinks
return FS.realpathSync(javaExe);
}
}
return null;
}
type Getter<T> = () => T;
function memoize<T>(getter : Getter<T>) : Getter<T> {
let computed : boolean = false;
let value : T | null = null;
return () => {
if (!computed) {
value = getter();
computed = true;
}
return value;
};
}
const TOOLS_JAR_PATHS : string[][] = [
["lib", "tools.jar"],
["..", "lib", "tools.jar"]
];
class JVMImpl implements JVM {
javaHome : string
javaExe : string
version : number
toolsJar: () => string | null;
constructor(javaHome : string, javaExe : string, version : number) {
this.javaHome = javaHome;
this.javaExe = javaExe;
this.version = version;
this.toolsJar = memoize(() => this.findToolsJar());
}
getJavaHome() : string {
return this.javaHome;
}
findToolsJar() : string | null {
if (this.version>=9) {
return null;
}
let javaHome = this.getJavaHome();
for (var tjp of TOOLS_JAR_PATHS) {
let toolsJar = Path.resolve(javaHome, ...tjp);
if (FS.existsSync(toolsJar)) {
return toolsJar;
}
}
//Not found.
return null;
}
getMajorVersion() {
return this.version;
}
getJavaExecutable(): string {
return this.javaExe;
}
isJdk(): boolean {
//Consider memoizing?
if (this.version<9) {
return this.getToolsJar()!=null;
} else {
return FS.existsSync(Path.resolve(this.getJavaHome(), "jmods", "jdk.management.jmod"));
}
}
getToolsJar(): string {
return this.toolsJar();
}
jarLaunch(jar: string, vmargs?: [string], execFileOptions?: ChildProcess.ExecFileOptions): ChildProcess.ChildProcess {
let args = [];
let toolsJar = this.getToolsJar();
if (toolsJar) {
args.push("-Dloader.path="+toolsJar);
}
if (vmargs) {
args.push(...vmargs);
}
args.push("-jar", jar);
return ChildProcess.execFile(this.getJavaExecutable(), args, execFileOptions);
}
mainClassLaunch(mainClass: string, classpath: string[], jvmArgs: string[], execFileOptions?: ChildProcess.ExecFileOptions): ChildProcess.ChildProcess {
const args: string[] = [];
// Classpath
args.push('-cp');
let classpathStr = classpath.join(Path.delimiter);
const toolsJar = this.getToolsJar();
if (toolsJar) {
classpathStr += Path.delimiter + toolsJar;
}
args.push(classpathStr);
// JVM Arguments
args.push(...jvmArgs);
// Main class
args.push(mainClass);
return ChildProcess.execFile(this.getJavaExecutable(), args, execFileOptions);
}
}
function getJavaInfo(javaExe : string) : Promise<Map<string, string>> {
//console.log("Fetching java properties for "+javaExe);
return new Promise((resolve, reject) => {
ChildProcess.execFile(javaExe, ['-XshowSettings:properties'], {}, (error, stdout, stderr) => {
let lines = stderr.split(/\r?\n/);
let propNames = [ 'java.version', 'java.home' ];
let props = new Map<string,string>();
for (var l of lines) {
//console.log("Line: "+l);
for (var p of propNames) {
let offset = l.indexOf(p);
if (offset>=0) {
//Make sure it looks like a proper 'assignment' to the property and not an
// accidental match.
//console.log("Propname found: "+p);
let assign = " " +p + " = ";
offset = l.indexOf(assign);
if (offset>=0) {
//console.log("Assignment found: "+p);
offset = offset + assign.length;
let value = l.substring(offset);
//console.log("value = "+value);
props.set(p, value);
if (props.size >= propNames.length) {
//We found everything we care about, so we can stop now.
//console.log("result = ", props);
return resolve(props);
}
}
}
}
}
//Not found everything we expected.
return reject("Unexpected output from `java -XshowSettings:properties`. Didn't find all expected properties: "+propNames);
});
});
}
function getMajorVersion(javaProperties : Map<string,string>) : number {
let versionString = javaProperties.get('java.version');
let pieces = versionString.split(".");
let major = parseInt(pieces[0]);
return major==1 ? parseInt(pieces[1]) : major;
}
function correctBinname(binname: string) {
if (process.platform === 'win32')
return binname + '.exe';
else
return binname;
}