Improvements to multi-threaded debugging

Separate out thread-specific parts
Only pause event thread for step, bp and thread events
Continue now resumes the specified thread instead of all threads
Prioritise stepping thread to prevent context switching during step
Monitor thread starts/ends

src/globals.js

@@ -0,0 +1,71 @@
+'use strict'
+
+const path = require('path');
+
+// some commonly used Java types in debugger-compatible format
+const JTYPES = {
+    byte: {typename:'byte',signature:'B'},
+    short: {typename:'short',signature:'S'},
+    int: {typename:'int',signature:'I'},
+    long: {typename:'long',signature:'J'},
+    float: {typename:'float',signature:'F'},
+    double: {typename:'double',signature:'D'},
+    char: {typename:'char',signature:'C'},
+    boolean: {typename:'boolean',signature:'Z'},
+    null: {typename:'null',signature:'Lnull;'},   // null has no type really, but we need something for literals
+    String: {typename:'String',signature:'Ljava/lang/String;'},
+    Object: {typename:'Object',signature:'Ljava/lang/Object;'},
+    isArray(t) { return t.signature[0]==='[' },
+    isObject(t) { return t.signature[0]==='L' },
+    isReference(t) { return /^[L[]/.test(t.signature) },
+    isPrimitive(t) { return !JTYPES.isReference(t.signature) },
+    isInteger(t) { return /^[BCIJS]$/.test(t.signature) },
+    isNumber(t) { return /^[BCIJSFD]$/.test(t.signature) },
+    isString(t) { return t.signature === this.String.signature },
+    isChar(t) { return t.signature === this.char.signature },
+    isBoolean(t) { return t.signature === this.boolean.signature },
+    fromPrimSig(sig) { return JTYPES['byte,short,int,long,float,double,char,boolean'.split(',')['BSIJFDCZ'.indexOf(sig)]] },
+}
+
+// the special name given to exception message fields
+const exmsg_var_name = ':msg';  
+
+function createJavaString(dbgr, s, opts) {
+    const raw = (opts && opts.israw) ? s : s.slice(1,-1).replace(/\\u[0-9a-fA-F]{4}|\\./,decode_char);
+    // return a deferred, which resolves to a local variable named 'literal'
+    return dbgr.createstring(raw);
+}
+
+function decode_char(c) {
+    switch(true) {
+        case /^\\[^u]$/.test(c):
+            // backslash escape
+            var x = {b:'\b',f:'\f',r:'\r',n:'\n',t:'\t',v:'\v','0':String.fromCharCode(0)}[c[1]];
+            return x || c[1];
+        case /^\\u[0-9a-fA-F]{4}$/.test(c):
+            // unicode escape
+            return String.fromCharCode(parseInt(c.slice(2),16));
+        case c.length===1 : 
+            return c;
+    }
+    throw new Error('Invalid character value');
+}
+
+function ensure_path_end_slash(p) {
+    return p + (/[\\/]$/.test(p) ? '' : path.sep);
+}
+
+function is_subpath_of(fpn, subpath) {
+    if (!subpath || !fpn) return false;
+    subpath = ensure_path_end_slash(''+subpath);
+    return fpn.slice(0,subpath.length) === subpath;
+}
+
+function variableRefToThreadId(variablesReference) {
+    return (variablesReference / 1e9)|0;
+}
+
+
+Object.assign(exports, {
+    JTYPES,exmsg_var_name,ensure_path_end_slash,is_subpath_of,decode_char,variableRefToThreadId,createJavaString
+});