Example usage for org.objectweb.asm MethodVisitor visitVarInsn

List of usage examples for org.objectweb.asm MethodVisitor visitVarInsn

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Introduction

In this page you can find the example usage for org.objectweb.asm MethodVisitor visitVarInsn.

Prototype

public void visitVarInsn(final int opcode, final int var)

Source Link

Document

Visits a local variable instruction.

Usage

From source file:com.nginious.http.xsp.StaticPart.java

License:Apache License

/**
 * Creates bytecode for this static part using the specified  class writer and method visitor. If this static
 * part is an expression a separate method is created with bytecode to evaluate the expression.
 * // w  w  w  . ja va  2s  . c o  m
 * @param intClassName the binary class name of the class being created
 * @param writer the class writer
 * @param visitor the method visitor
 * @throws XspException if unable to create bytecode
 */
void compile(String intClassName, ClassWriter writer, MethodVisitor visitor) throws XspException {
    if (isExpression()) {
        this.methodName = "staticExpr" + methodNameCounter.getAndIncrement();
        visitor.visitVarInsn(Opcodes.ALOAD, 0);
        visitor.visitVarInsn(Opcodes.ALOAD, 3);
        visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, intClassName, this.methodName,
                "(Ljava/lang/StringBuffer;)V");
        compileMethod(intClassName, writer);
    } else {
        String contentStr = new String(content, start, len);
        visitor.visitVarInsn(Opcodes.ALOAD, 3);
        visitor.visitLdcInsn(contentStr);
        visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append",
                "(Ljava/lang/String;)Ljava/lang/StringBuffer;");
        visitor.visitInsn(Opcodes.POP);
    }
}

From source file:com.nginious.http.xsp.StaticPart.java

License:Apache License

/**
 * Creates bytecode in a separate method for evaluating an expression.
 * /*from   w w w  .ja  va 2s  . c om*/
 * @param intClassName the binary class name of the class being created
 * @param writer the class writer
 * @throws XspException if unable to create bytecode
 */
void compileMethod(String intClassName, ClassWriter writer) throws XspException {
    if (!isExpression()) {
        return;
    }

    try {
        ExpressionParser parser = new ExpressionParser();
        TreeExpression expr = parser.parse(getExpressionContent());

        MethodVisitor visitor = writer.visitMethod(Opcodes.ACC_PRIVATE, this.methodName,
                "(Ljava/lang/StringBuffer;)V", null, null);
        visitor.visitCode();
        visitor.visitVarInsn(Opcodes.ALOAD, 1);

        if (expr.getType() == Type.ANY) {
            expr.compile(visitor, Type.STRING);
        } else {
            expr.compile(visitor);
        }

        if (expr.getType() == Type.BOOLEAN) {
            visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append",
                    "(Z)Ljava/lang/StringBuffer;");
        } else if (expr.getType() == Type.DOUBLE) {
            visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append",
                    "(D)Ljava/lang/StringBuffer;");
        } else if (expr.getType() == Type.INT) {
            visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append",
                    "(I)Ljava/lang/StringBuffer;");
        } else if (expr.getType() == Type.STRING || expr.getType() == Type.ANY) {
            visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append",
                    "(Ljava/lang/String;)Ljava/lang/StringBuffer;");
        }

        visitor.visitInsn(Opcodes.POP);
        visitor.visitInsn(Opcodes.RETURN);
        visitor.visitMaxs(5, 5);
        visitor.visitEnd();
    } catch (ExpressionException e) {
        throw new XspException("Invalid expression at " + getLocationDescriptor(), e);
    }
}

From source file:com.nginious.http.xsp.XspCompiler.java

License:Apache License

/**
 * Creates subclass of {@link XspService} for the XSP file represented by the specified document
 * tree node structure.//from w  ww  .j  a va  2s  .  c o  m
 * 
 * @param document the document tree node structure
 * @param srcFilePath the XSP file source path
 * @return a descriptor for the generated subclass
 * @throws XspException if unable to create subclass
 */
private ClassDescriptor compileService(DocumentPart document, String srcFilePath) throws XspException {
    ClassWriter writer = new ClassWriter(0);

    // Create class
    String packageName = document.getMetaContent("package");
    String intServiceClazzName = createIntServiceClassName(packageName, srcFilePath);
    String serviceClazzName = createServiceClassName(packageName, srcFilePath);
    writer.visit(Opcodes.V1_6, Opcodes.ACC_PUBLIC, intServiceClazzName, "Lcom/nginious/http/xsp/XspService;",
            "com/nginious/http/xsp/XspService", null);

    // Create constructor
    createConstructor(writer, "com/nginious/http/xsp/XspService");

    // Create xsp service method
    MethodVisitor visitor = createXspMethod(writer);

    Label tryLabel = new Label();
    Label startCatchLabel = new Label();
    Label endCatchLabel = new Label();

    // Start try block
    visitor.visitTryCatchBlock(tryLabel, startCatchLabel, endCatchLabel, "java/lang/Throwable");

    visitor.visitLabel(tryLabel);

    visitor.visitTypeInsn(Opcodes.NEW, "com/nginious/http/xsp/expr/HttpRequestVariables");
    visitor.visitInsn(Opcodes.DUP);
    visitor.visitVarInsn(Opcodes.ALOAD, 1);
    visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, "com/nginious/http/xsp/expr/HttpRequestVariables", "<init>",
            "(Lcom/nginious/http/HttpRequest;)V");
    visitor.visitMethodInsn(Opcodes.INVOKESTATIC, "com/nginious/http/xsp/expr/Expression", "setVariables",
            "(Lcom/nginious/http/xsp/expr/Variables;)V");

    document.compile(intServiceClazzName, writer, visitor);

    visitor.visitLabel(startCatchLabel);
    visitor.visitMethodInsn(Opcodes.INVOKESTATIC, "com/nginious/http/xsp/expr/Expression", "removeVariables",
            "()V");

    visitor.visitLdcInsn(true);
    visitor.visitInsn(Opcodes.IRETURN);

    // Start finally block
    visitor.visitLabel(endCatchLabel);
    visitor.visitMethodInsn(Opcodes.INVOKESTATIC, "com/nginious/http/xsp/expr/Expression", "removeVariables",
            "()V");
    visitor.visitInsn(Opcodes.ATHROW);

    visitor.visitMaxs(12, 12);
    visitor.visitEnd();

    document.compileMethod(intServiceClazzName, writer);

    writer.visitEnd();
    byte[] clazzBytes = writer.toByteArray();
    return new ClassDescriptor(serviceClazzName, clazzBytes);
}

From source file:com.nginious.http.xsp.XspCompiler.java

License:Apache License

/**
 * Creates a constructor with no arguments for the XSP service class being created with the
 * specified class writer. Bytecode is created for calling the superclass constructor in the
 * superclass with the specified supperclass name.
 * /*  w  ww. ja  va 2s  .co m*/
 * @param writer the class writer
 * @param superclassName the superclass name
 * @see XspService
 */
void createConstructor(ClassWriter writer, String superclassName) {
    MethodVisitor visitor = writer.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
    visitor.visitCode();
    visitor.visitVarInsn(Opcodes.ALOAD, 0);
    visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, superclassName, "<init>", "()V");
    visitor.visitInsn(Opcodes.RETURN);
    visitor.visitMaxs(1, 1);
    visitor.visitEnd();
}

From source file:com.nway.spring.jdbc.bean.AsmBeanProcessor.java

License:Apache License

/**
 *
 *
 * @param mv ${@link MethodVisitor}/*from  w  w  w .  ja va2  s . c o  m*/
 * @param index rs.getDate(index)
 * @param beanSignature com/nway/commons/dbutils/test/User
 * @param rsTypeDesc Ljava/sql/Date;
 * @param beanTypeDesc Ljava/util/Date;
 * @param rsMethod getDate
 * @param writeMethod setDate
 */
private void visitMethod(MethodVisitor mv, int index, String beanSignature, String beanTypeDesc,
        String rsMethod, String writeMethod) {

    mv.visitVarInsn(Opcodes.ALOAD, 3);
    mv.visitVarInsn(Opcodes.ALOAD, 1);

    visitInsn(mv, index);

    mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", rsMethod, "(I)" + beanTypeDesc, true);
    mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(" + beanTypeDesc + ")V", false);
}

From source file:com.nway.spring.jdbc.bean.AsmBeanProcessor.java

License:Apache License

private void visitMethodCast(MethodVisitor mv, int index, String beanSignature, int beanType,
        String beanTypeDesc, String writeMethod) {

    mv.visitVarInsn(Opcodes.ALOAD, 3);
    mv.visitVarInsn(Opcodes.ALOAD, 1);/*from w w w . j a v  a2s.  c  o m*/

    visitInsn(mv, index);

    switch (beanType) {
    case PROPERTY_TYPE_DATE:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getTimestamp",
                "(I)Ljava/sql/Timestamp;", true);
        break;
    default:
        mv.visitMethodInsn(Opcodes.INVOKESTATIC, "org/springframework/jdbc/support/JdbcUtils",
                "getResultSetValue", "(Ljava/sql/ResultSet;I)Ljava/lang/Object;", false);
        mv.visitTypeInsn(Opcodes.CHECKCAST, beanTypeDesc);
        break;
    }

    mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(L" + beanTypeDesc + ";)V", false);
}

From source file:com.nway.spring.jdbc.bean.AsmBeanProcessor.java

License:Apache License

private void visitMethodWrap(MethodVisitor mv, int index, String beanSignature, int beanType,
        String writeMethod, String processorName) {

    mv.visitVarInsn(Opcodes.ALOAD, 3);
    mv.visitVarInsn(Opcodes.ALOAD, 0);//from  w ww  . j  a va2  s.c  om
    mv.visitVarInsn(Opcodes.ALOAD, 1);

    visitInsn(mv, index);

    switch (beanType) {
    case PROPERTY_TYPE_INTEGER:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getInt", "(I)I", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "integerValue", "(IZ)Ljava/lang/Integer;",
                false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Integer;)V", false);
        break;
    case PROPERTY_TYPE_LONG:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getLong", "(I)J", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "longValue", "(JZ)Ljava/lang/Long;", false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Long;)V", false);
        break;
    case PROPERTY_TYPE_BOOLEAN:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getBoolean", "(I)Z", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "booleanValue", "(ZZ)Ljava/lang/Boolean;",
                false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Boolean;)V", false);
        break;
    case PROPERTY_TYPE_FLOAT:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getFloat", "(I)F", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "floatValue", "(FZ)Ljava/lang/Float;", false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Float;)V", false);
        break;
    case PROPERTY_TYPE_DOUBLE:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getDouble", "(I)D", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "doubleValue", "(DZ)Ljava/lang/Double;",
                false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Double;)V", false);
        break;
    case PROPERTY_TYPE_BYTE:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getByte", "(I)B", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "byteValue", "(BZ)Ljava/lang/Byte;", false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Byte;)V", false);
        break;
    case PROPERTY_TYPE_SHORT:
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "getShort", "(I)S", true);
        mv.visitVarInsn(Opcodes.ALOAD, 1);
        mv.visitMethodInsn(Opcodes.INVOKEINTERFACE, "java/sql/ResultSet", "wasNull", "()Z", true);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, processorName, "shortValue", "(SZ)Ljava/lang/Short;", false);
        mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, beanSignature, writeMethod, "(Ljava/lang/Short;)V", false);
        break;
    }
}

From source file:com.nway.spring.jdbc.bean.AsmBeanProcessor.java

License:Apache License

/**
 *
 * //from  w  ww .java  2  s  .c o m
 *
 * @param cw
 * @param mv
 * @param processorName com/nway/commons/dbutils/DynamicBeanProcessorImpl
 * @param beanName com/nway/commons/dbutils/test/User
 * @return [0]:bean[1]createBean
 */
private Object[] prepScript(ClassWriter cw, MethodVisitor mv, String processorName, String beanName) {

    Object[] lab = new Object[2];

    cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC + Opcodes.ACC_SUPER, processorName, null,
            "com/nway/spring/jdbc/bean/DbBeanFactory", null);

    cw.visitSource(processorName.substring(processorName.lastIndexOf('/') + 1) + ".java", null);

    {
        mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
        mv.visitCode();
        Label l0 = new Label();
        mv.visitLabel(l0);
        mv.visitLineNumber(6, l0);
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitMethodInsn(Opcodes.INVOKESPECIAL, "com/nway/spring/jdbc/bean/DbBeanFactory", "<init>", "()V",
                false);
        mv.visitInsn(Opcodes.RETURN);
        Label l1 = new Label();
        mv.visitLabel(l1);
        mv.visitLocalVariable("this", "L" + processorName + ";", null, l0, l1, 0);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
    }
    {
        mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "createBean",
                "(Ljava/sql/ResultSet;Ljava/lang/Class;)Ljava/lang/Object;",
                "<T:Ljava/lang/Object;>(Ljava/sql/ResultSet;Ljava/lang/Class<TT;>;)TT;",
                new String[] { "java/sql/SQLException" });
        mv.visitCode();
        Label l0 = new Label();
        mv.visitLabel(l0);
        mv.visitLineNumber(10, l0);
        mv.visitTypeInsn(Opcodes.NEW, beanName);
        mv.visitInsn(Opcodes.DUP);
        mv.visitMethodInsn(Opcodes.INVOKESPECIAL, beanName, "<init>", "()V", false);
        mv.visitVarInsn(Opcodes.ASTORE, 3);

        lab[0] = l0;
        lab[1] = mv;
    }

    return lab;
}

From source file:com.nway.spring.jdbc.bean.AsmBeanProcessor.java

License:Apache License

/**
 *
 * /*from ww w.j a  va  2  s .  c o m*/
 *
 * @param mv MethodVisitor
 * @param processorName com/nway/commons/dbutils/DynamicBeanProcessorImpl
 * @param beanName com/nway/commons/dbutils/test/User
 */
private void endScript(MethodVisitor mv, Label processorLabel, Label beanStart, int lineNumber,
        String processorName, String beanName) {

    Label l10 = new Label();
    mv.visitLabel(l10);
    mv.visitLineNumber(lineNumber, l10);
    mv.visitVarInsn(Opcodes.ALOAD, 3);
    mv.visitInsn(Opcodes.ARETURN);
    Label l11 = new Label();
    mv.visitLabel(l11);
    mv.visitLocalVariable("this", "L" + processorName + ";", null, processorLabel, l11, 0);
    mv.visitLocalVariable("rs", "Ljava/sql/ResultSet;", null, processorLabel, l11, 1);
    mv.visitLocalVariable("type", "Ljava/lang/Class;", "Ljava/lang/Class<TT;>;", processorLabel, l11, 2);
    mv.visitLocalVariable("bean", "L" + beanName + ";", null, beanStart, l11, 3);
    mv.visitMaxs(5, 4);
    mv.visitEnd();
}

From source file:com.openpojo.reflection.java.bytecode.asm.SubClassCreator.java

License:Open Source License

/**
 * This method will copy over the constructors to the subclass.
 */// ww w. java 2s.  c o  m
@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
    LOGGER.debug("Method: " + name + " access:" + access + " desc:" + desc + " signature:" + signature
            + " exceptions:" + Arrays.toString(exceptions));
    if (name.equals("<init>") && access == ACC_PUBLIC || access == ACC_PROTECTED) {
        MethodVisitor mv = cw.visitMethod(access, name, desc, signature, exceptions);
        int counter = getParameterCount(desc);
        // wire constructor method to super
        {
            mv.visitCode();
            for (int idx = 0; idx <= counter; idx++) {
                mv.visitVarInsn(ALOAD, idx);
            }
            mv.visitMethodInsn(INVOKESPECIAL, className.replace(Java.PACKAGE_DELIMITER, Java.PATH_DELIMITER),
                    "<init>", desc, false);
            mv.visitInsn(RETURN);
            mv.visitMaxs(counter + 1, counter + 1);
            mv.visitEnd();
        }
    }

    return super.visitMethod(access, name, desc, signature, exceptions);
}