Examples with MethodBuilder org.apache.derby.iapi.services.compiler.MethodBuilder used on opensource projects

Example 31 with MethodBuilder

use of org.apache.derby.iapi.services.compiler.MethodBuilder in project derby by apache.

the class UnaryOperatorNode method addXmlOpMethodParams.

/**
 * Add some additional arguments to our method call for
 * XML related operations like XMLPARSE and XMLSERIALIZE.
 *
 * @param acb the builder for the class in which the method lives
 * @param mb The MethodBuilder that will make the call.
 * @param resultField the field that contains the previous result
 * @return Number of parameters added.
 */
int addXmlOpMethodParams(ExpressionClassBuilder acb, MethodBuilder mb, LocalField resultField) throws StandardException {
    if ((kind != K_XMLPARSE) && (kind != K_XMLSERIALIZE)) {
        // nothing to do.
        return 0;
    }
    if (kind == K_XMLSERIALIZE) {
        // We push the target type's JDBC type id as well as
        // the maximum width, since both are required when
        // we actually perform the operation, and both are
        // primitive types.  Note: we don't have to save
        // any objects for XMLSERIALIZE because it doesn't
        // require any XML-specific objects: it just returns
        // the serialized version of the XML value, which we
        // already found when the XML value was created (ex.
        // as part of the XMLPARSE work).
        // We also need to pass the collation type of the current
        // compilation schema. If the JDBC type id is of type
        // StringDataValue, then we should use the collation to
        // decide whether we need to generate collation sensitive
        // StringDataValue.
        mb.push(targetType.getJDBCTypeId());
        mb.push(targetType.getMaximumWidth());
        mb.push(getSchemaDescriptor(null, false).getCollationType());
        return 3;
    }
    /* Else we're here for XMLPARSE. */
    // XMLPARSE is different from other unary operators in that the method
    // must be called on the result object (the XML value) and not on the
    // operand (the string value). We must therefore make sure the result
    // object is not null.
    MethodBuilder constructor = acb.getConstructor();
    acb.generateNull(constructor, getTypeCompiler(), getTypeServices().getCollationType());
    constructor.setField(resultField);
    // Swap operand and result object so that the method will be called
    // on the result object.
    mb.swap();
    // Push whether or not we want to preserve whitespace.
    mb.push(preserveWhitespace);
    // Push the SqlXmlUtil instance as the next argument.
    pushSqlXmlUtil(acb, mb, null, null);
    return 2;
}

Example 32 with MethodBuilder

use of org.apache.derby.iapi.services.compiler.MethodBuilder in project derby by apache.

the class CurrentOfNode method generate.

/**
 * Generation on a CurrentOfNode creates a scan on the
 * cursor, CurrentOfResultSet.
 * <p>
 * This routine will generate and return a call of the form:
 * <pre><verbatim>
 *	 	ResultSetFactory.getCurrentOfResultSet(cursorName)
 *	   </verbatim></pre>
 *
 * @param acb	The ActivationClassBuilder for the class being built
 * @param mb	The execute() method to be built
 *
 * @exception StandardException		Thrown on error
 */
@Override
void generate(ActivationClassBuilder acb, MethodBuilder mb) throws StandardException {
    if (SanityManager.DEBUG)
        SanityManager.ASSERT(!isStatementResultSet(), "CurrentOfNode not expected to be statement node");
    /* Get the next ResultSet #, so that we can number this ResultSetNode, its
		 * ResultColumnList and ResultSet.
		 */
    assignResultSetNumber();
    // for the putField
    mb.pushThis();
    // The generated java returned by this method is the expression:
    // ResultSetFactory.getCurrentOfResultSet(
    // #cursorName(), this, resultSetNumber)
    acb.pushGetResultSetFactoryExpression(mb);
    mb.push(cursorName);
    acb.pushThisAsActivation(mb);
    mb.push(getResultSetNumber());
    mb.callMethod(VMOpcode.INVOKEINTERFACE, (String) null, "getCurrentOfResultSet", ClassName.NoPutResultSet, 3);
    mb.cast(ClassName.CursorResultSet);
    // the current of scan generator is what we return
    /* This table is the target of an update or a delete, so we must 
		 * wrap the Expression up in an assignment expression before 
		 * returning. Delete or update use the field that is set
		 * to calculate the CurrentRowLocation value.
		 * NOTE - scanExpress is a ResultSet.  We will need to cast it to the
		 * appropriate subclass.
		 * For example, for a DELETE, instead of returning a call to the 
		 * ResultSetFactory, we will generate and return:
		 *		this.SCANRESULTSET = (cast to appropriate ResultSet type) 
		 * The outer cast back to ResultSet is needed so that
		 * we invoke the appropriate method in the call to the ResultSetFactory
		 */
    mb.putField((String) null, acb.getRowLocationScanResultSetName(), ClassName.CursorResultSet);
    mb.cast(ClassName.NoPutResultSet);
    // add a check at activation reset time to see if the cursor has
    // changed underneath us. Doing it in the constructor allows the
    // compilation to happen
    MethodBuilder rmb = acb.startResetMethod();
    rmb.pushThis();
    rmb.push(cursorName);
    rmb.push(preStmt.getObjectName());
    rmb.callMethod(VMOpcode.INVOKEVIRTUAL, ClassName.BaseActivation, "checkPositionedStatement", "void", 2);
    rmb.methodReturn();
    rmb.complete();
}

Example 33 with MethodBuilder

use of org.apache.derby.iapi.services.compiler.MethodBuilder in project derby by apache.

the class CurrentRowLocationNode method generateExpression.

/**
 * CurrentRowLocationNode is used in updates and deletes.  See generate() in
 * UpdateNode and DeleteNode to get the full overview of generate().  This
 * class is responsible for generating the method that will return the RowLocation
 * for the next row to be updated or deleted.
 *
 * This routine will generate a method of the form:
 *
 *		private SQLRef	fieldx;
 *
 *		...
 *
 *      protected DataValueDescriptor exprx()
 *				throws StandardException
 *		{
 *			return fieldx = <SQLRefConstructor>(
 *									"result set member".getRowLocation(),
 *									fieldx);
 *		}
 * and return the generated code:
 *    exprx()
 *
 * ("result set member" is a member of the generated class added by UpdateNode or
 * DeleteNode.)
 * This exprx function is used within another exprx function,
 * and so doesn't need a static field or to be public; but
 * at present, it has both.
 *
 * fieldx is a generated field that is initialized to null when the
 * activation is constructed.  getSQLRef will re-use fieldx on calls
 * after the first call, rather than allocate a new SQLRef for each call.
 *
 * @param acb	The ExpressionClassBuilder for the class being built
 *
 * @exception StandardException		Thrown on error
 */
@Override
void generateExpression(ExpressionClassBuilder acb, MethodBuilder mbex) throws StandardException {
    /* Generate a new method */
    /* only used within the other exprFuns, so can be private */
    MethodBuilder mb = acb.newGeneratedFun(ClassName.DataValueDescriptor, Modifier.PROTECTED);
    /* Allocate an object for re-use to hold the result of the operator */
    LocalField field = acb.newFieldDeclaration(Modifier.PRIVATE, ClassName.RefDataValue);
    /* Fill in the body of the method
		 * generates:
		 *    return TypeFactory.getSQLRef(this.ROWLOCATIONSCANRESULTSET.getRowLocation());
		 * and adds it to exprFun
		 */
    mb.pushThis();
    mb.getField((String) null, acb.getRowLocationScanResultSetName(), ClassName.CursorResultSet);
    mb.callMethod(VMOpcode.INVOKEINTERFACE, (String) null, "getRowLocation", ClassName.RowLocation, 0);
    acb.generateDataValue(mb, getTypeCompiler(), getTypeServices().getCollationType(), field);
    /*
		** Store the result of the method call in the field, so we can re-use
		** the object.
		*/
    mb.putField(field);
    /* Stuff the full expression into a return statement and add that to the
		 * body of the new method.
		 */
    mb.methodReturn();
    // complete the method
    mb.complete();
    /* Generate the call to the new method */
    mbex.pushThis();
    mbex.callMethod(VMOpcode.INVOKEVIRTUAL, (String) null, mb.getName(), ClassName.DataValueDescriptor, 0);
}

Example 34 with MethodBuilder

use of org.apache.derby.iapi.services.compiler.MethodBuilder in project derby by apache.

the class ActivationClassBuilder method startResetMethod.

// /////////////////////////////////////////////////////////////////////
// 
// EXECUTE METHODS
// 
// /////////////////////////////////////////////////////////////////////
MethodBuilder startResetMethod() {
    MethodBuilder mb = cb.newMethodBuilder(Modifier.PUBLIC, "void", "reset");
    mb.addThrownException(ClassName.StandardException);
    mb.pushThis();
    mb.callMethod(VMOpcode.INVOKESPECIAL, ClassName.BaseActivation, "reset", "void", 0);
    return mb;
}

Example 35 with MethodBuilder

use of org.apache.derby.iapi.services.compiler.MethodBuilder in project derby by apache.

the class ActivationClassBuilder method addCursorPositionCode.

// /////////////////////////////////////////////////////////////////////
// 
// CURSOR SUPPORT
// 
// /////////////////////////////////////////////////////////////////////
/**
 * Updatable cursors
 * need to add a getter method for use in BaseActivation to access
 * the result set that identifies target rows for a positioned
 * update or delete.
 * <p>
 * The code that is generated is:
 * <pre><verbatim>
 *  public CursorResultSet getTargetResultSet() {
 *	    return targetResultSet;
 *  }
 *
 *  public CursorResultSet getCursorResultSet() {
 *		return cursorResultSet;
 *  }
 * </verbatim></pre>
 */
void addCursorPositionCode() {
    // the getter
    // This method is an implementation of the interface method
    // CursorActivation - CursorResultSet getTargetResultSet()
    MethodBuilder getter = cb.newMethodBuilder(Modifier.PUBLIC, ClassName.CursorResultSet, "getTargetResultSet");
    getter.getField(targetResultSetField);
    getter.methodReturn();
    getter.complete();
    // This method is an implementation of the interface method
    // CursorActivation - CursorResultSet getCursorResultSet()
    getter = cb.newMethodBuilder(Modifier.PUBLIC, ClassName.CursorResultSet, "getCursorResultSet");
    getter.getField(cursorResultSetField);
    getter.methodReturn();
    getter.complete();
}