Groovy example source code file (MethodPatternsTest.groovy)

This example Groovy source code file (MethodPatternsTest.groovy) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

a, a, aload, dup, iadd, iconst_1, ifeq, ii, iload, iload, istore, istore, ldc, ldc

The Groovy MethodPatternsTest.groovy source code

package org.codehaus.groovy.classgen.asm


/**
 * @author Jochen Theodorou
 */
class MethodPatternsTest extends AbstractBytecodeTestCase {

    // make a test for native compilation of the ackerman function
    // and ensure the nested call is optimized
    void testAckerman() {
        assert compile(method: 'A', '''
                int A(int x, int y) {
                    if (x == 0) return y+1
                    if (y == 0) return A(x-1, 1)
                    return A(x-1, A(x, y-1))
                }
            ''').hasSequence([
                // if (x==0) return y+1
                'ILOAD 1',
                'LDC 0',
                'IF_ICMPNE',
                'ICONST_1',
                'ICONST_0',
                'IFEQ',     // x==0 and branching till here
                'ILOAD 2',
                'LDC 1',
                'IADD',     // y+1
                'IRETURN',  // return
                // if (y==0) return A(x-1,1)
                'ILOAD 2',
                'LDC 0',
                'IF_ICMPNE',
                'ICONST_1',
                'ICONST_0',
                'IFEQ',     // y==0 and branching till here
                'ALOAD 0',
                'ILOAD 1',
                'LDC 1',
                'ISUB',     // x-1 argument
                'LDC 1',
                'INVOKEVIRTUAL script.A (II)I', // A(x-1,1)
                'IRETURN',  //return
                // return A(x-1,A(x,y-1))
                'ALOAD 0',
                'ILOAD 1',
                'LDC 1',
                'ISUB',     // outer A x-1 argument
                'ALOAD 0',
                'ILOAD 1',  // inner A x argument
                'ILOAD 2',
                'LDC 1',
                'ISUB',     //inner A y-1 argument
                'INVOKEVIRTUAL script.A (II)I', // inner A
                'INVOKEVIRTUAL script.A (II)I', // outer A
                'IRETURN' //return
            ])
    }
    
    void testForLoopSettingArray() {
        assert compile('''
            int n = 10
            int[] x = new int[n]
            for (int i = 0; i < n; i++) x[i] = i + 1
        ''').hasSequence([
            'ILOAD',
            'ILOAD',
            'IF_ICMPGE',
            'ICONST_1',
            'GOTO',
            'ICONST_0',
            'IFEQ',
            'ILOAD',
            'LDC',
            'IADD',
            'ISTORE',
            'ALOAD',
            'ILOAD',
            'ILOAD',
            'INVOKESTATIC org/codehaus/groovy/runtime/BytecodeInterface8.intArraySet ([III)V',
            'ILOAD',
            'DUP',
            'ISTORE',
            'ICONST_1',
            'IADD',
            'DUP',
            'ISTORE 11',
            'POP',
            'GOTO'
        ])
    }
    
    void testForLoopSettingArrayWithOperatorUsedInAssignmentAndArrayRHS() {
        assert compile('''
            int n = 10
            int[] x = new int[n]
            int[] y = new int[n]
            for (int i = 0; i < n; i++) x[i] += y[i]
        ''').hasSequence ([
            'ILOAD',
            'ILOAD',
            'IF_ICMPGE',
            'ICONST_1',
            'GOTO',
            'ICONST_0',
            'IFEQ',
            'ILOAD',
            'ISTORE',
            'ALOAD',
            'DUP',
            'ILOAD',
            'INVOKESTATIC org/codehaus/groovy/runtime/BytecodeInterface8.intArrayGet ([II)I',
            'ALOAD',
            'ILOAD',
            'INVOKESTATIC org/codehaus/groovy/runtime/BytecodeInterface8.intArrayGet ([II)I',
            'IADD',
            'DUP',
            'ISTORE',
            'ILOAD',
            'SWAP',
            'INVOKESTATIC org/codehaus/groovy/runtime/BytecodeInterface8.intArraySet ([III)V',
            'ILOAD',
            'DUP',
            'ISTORE',
            'ICONST_1',
            'IADD',
            'ISTORE',
            'GOTO L14'
        ])
    }
}