memberresolver.java

Javassist是一个开源的分析、编辑和创建Java字节码的类库。是由东京技术学院的数学和计算机科学系的 Shigeru Chiba 所创建的。它已加入了开放源代码JBoss 应用服务器项目,通过使

            throw new NoFieldException(jvmClassName + "$" + field, expr);
        }
    }

    /**
     * @param jvmClassName  a JVM class name.  e.g. java/lang/String
     */
    public CtField lookupFieldByJvmName(String jvmClassName, Symbol fieldName)
        throws CompileError
    {
        return lookupField(jvmToJavaName(jvmClassName), fieldName);
    }

    /**
     * @param name      a qualified class name. e.g. java.lang.String
     */
    public CtField lookupField(String className, Symbol fieldName)
        throws CompileError
    {
        CtClass cc = lookupClass(className, false);
        try {
            return cc.getField(fieldName.get());
        }
        catch (NotFoundException e) {}
        throw new CompileError("no such field: " + fieldName.get());
    }

    public CtClass lookupClassByName(ASTList name) throws CompileError {
        return lookupClass(Declarator.astToClassName(name, '.'), false);
    }

    public CtClass lookupClassByJvmName(String jvmName) throws CompileError {
        return lookupClass(jvmToJavaName(jvmName), false);
    }

    public CtClass lookupClass(Declarator decl) throws CompileError {
        return lookupClass(decl.getType(), decl.getArrayDim(),
                           decl.getClassName());
    }

    /**
     * @parma classname         jvm class name.
     */
    public CtClass lookupClass(int type, int dim, String classname)
        throws CompileError
    {
        String cname = "";
        CtClass clazz;
        if (type == CLASS) {
            clazz = lookupClassByJvmName(classname);
            if (dim > 0)
                cname = clazz.getName();
            else
                return clazz;
        }
        else
            cname = getTypeName(type);

        while (dim-- > 0)
            cname += "[]";

        return lookupClass(cname, false);
    }

    /*
     * type cannot be CLASS
     */
    static String getTypeName(int type) throws CompileError {
        String cname = "";
        switch (type) {
        case BOOLEAN :
            cname = "boolean";
            break;
        case CHAR :
            cname = "char";
            break;
        case BYTE :
            cname = "byte";
            break;
        case SHORT :
            cname = "short";
            break;
        case INT :
            cname = "int";
            break;
        case LONG :
            cname = "long";
            break;
        case FLOAT :
            cname = "float";
            break;
        case DOUBLE :
            cname = "double";
            break;
        case VOID :
            cname = "void";
            break;
        default :
            fatal();
        }

        return cname;
    }

    /**
     * @param name      a qualified class name. e.g. java.lang.String
     */
    public CtClass lookupClass(String name, boolean notCheckInner)
        throws CompileError
    {
        try {
            return lookupClass0(name, notCheckInner);
        }
        catch (NotFoundException e) {
            return searchImports(name);
        }
    }

    private CtClass searchImports(String orgName)
        throws CompileError
    {
        if (orgName.indexOf('.') < 0) {
            Iterator it = classPool.getImportedPackages();
            while (it.hasNext()) {
                String pac = (String)it.next();
                String fqName = pac + '.' + orgName;
                try {
                    CtClass cc = classPool.get(fqName);
                    // if the class is found,
                    classPool.recordInvalidClassName(orgName);
                    return cc;
                }
                catch (NotFoundException e) {
                    classPool.recordInvalidClassName(fqName);
                }
            }
        }

        throw new CompileError("no such class: " + orgName);
    }

    private CtClass lookupClass0(String classname, boolean notCheckInner)
        throws NotFoundException
    {
        CtClass cc = null;
        do {
            try {
                cc = classPool.get(classname);
            }
            catch (NotFoundException e) {
                int i = classname.lastIndexOf('.');
                if (notCheckInner || i < 0)
                    throw e;
                else {
                    StringBuffer sbuf = new StringBuffer(classname);
                    sbuf.setCharAt(i, '$');
                    classname = sbuf.toString();
                }
            }
        } while (cc == null);
        return cc;
    }

    /* Converts a class name into a JVM-internal representation.
     *
     * It may also expand a simple class name to java.lang.*.
     * For example, this converts Object into java/lang/Object.
     */
    public String resolveClassName(ASTList name) throws CompileError {
        if (name == null)
            return null;
        else
            return javaToJvmName(lookupClassByName(name).getName());
    }

    /* Expands a simple class name to java.lang.*.
     * For example, this converts Object into java/lang/Object.
     */
    public String resolveJvmClassName(String jvmName) throws CompileError {
        if (jvmName == null)
            return null;
        else
            return javaToJvmName(lookupClassByJvmName(jvmName).getName());
    }

    public static CtClass getSuperclass(CtClass c) throws CompileError {
        try {
            CtClass sc = c.getSuperclass();
            if (sc != null)
                return sc;
        }
        catch (NotFoundException e) {}
        throw new CompileError("cannot find the super class of "
                               + c.getName());
    }

    public static String javaToJvmName(String classname) {
        return classname.replace('.', '/');
    }

    public static String jvmToJavaName(String classname) {
        return classname.replace('/', '.');
    }

    public static int descToType(char c) throws CompileError {
        switch (c) {
        case 'Z' :
            return BOOLEAN;
        case 'C' :
            return CHAR;
        case 'B' :
            return  BYTE;
        case 'S' :
            return SHORT;
        case 'I' :
            return INT;
        case 'J' :
            return LONG;
        case 'F' :
            return FLOAT;
        case 'D' :
            return DOUBLE;
        case 'V' :
            return VOID;
        case 'L' :
        case '[' :
            return CLASS;
        default :
            fatal();
            return VOID;    // never reach here
        }
    }

    public static int getModifiers(ASTList mods) {
        int m = 0;
        while (mods != null) {
            Keyword k = (Keyword)mods.head();
            mods = mods.tail();
            switch (k.get()) {
            case STATIC :
                m |= Modifier.STATIC;
                break;
            case FINAL :
                m |= Modifier.FINAL;
                break;
            case SYNCHRONIZED :
                m |= Modifier.SYNCHRONIZED;
                break;
            case ABSTRACT :
                m |= Modifier.ABSTRACT;
                break;
            case PUBLIC :
                m |= Modifier.PUBLIC;
                break;
            case PROTECTED :
                m |= Modifier.PROTECTED;
                break;
            case PRIVATE :
                m |= Modifier.PRIVATE;
                break;
            case VOLATILE :
                m |= Modifier.VOLATILE;
                break;
            case TRANSIENT :
                m |= Modifier.TRANSIENT;
                break;
            case STRICT :
                m |= Modifier.STRICT;
                break;
            }
        }

        return m;
    }
}