Executing a decision operation

If the decision service archives are accessible at give URLs, you can use URLDecisionRunnerProvider:

URL url = ...;
DecisionRunnerProvider provider = new URLDecisionRunnerProvider
   .Builder()
   .addURL(urlToDSA1)
   .addURL(urlToDSA2)
   .build();

If the decision service archives are added to the class path of the application, you can use ClassLoaderRunnerProvider:

DecisionRunnerProvider provider = new ClassLoaderDecisionRunnerProvider
   .Builder()
   .build();

The lookup strategy for the decision service archive is to first search in the thread context class loader, then in the class loader that loads the classes of the API.

You can also specify the class loader that contains the decision service archive:

ClassLoader cl = ..; // classloader containig the DSA
DecisionRunnerProvider provider = new ClassLoaderDecisionRunnerProvider
   .Builder()
   .withClassLoader(cl)
   .build();

For an instance of DecisionRunnerProvider, the engine runtime version for all decision service archives must be the same.

To obtain a DecisionRunner instance for the decision operation operationName:

String operationName = ..; // the name of an operation
DecisionRunner runner = provider.getDecisionRunner(operationName);

To execute a decision operation named LoanValidation by using Java objects as input and output:

DecisionRunnerProvider provider = ...;
DecisionRunner runner = provider.getDecisionRunner("LoanValidation");
Object in = ...;
Object out = runner.execute(in);

Here is a complete example for executing a decision operation of the decision service Loan Approval in the Banking sample decision automation. Add the decision service archive loanApproval-<version>.jar to the application class path. This decision service archive is in the archives folder in the GitHub repository for samples and tutorials. For more information, see Samples and tutorials in GitHub.

import com.ibm.decision.run.DecisionRunner;
import com.ibm.decision.run.provider.ClassLoaderDecisionRunnerProvider;
import com.ibm.decision.run.provider.DecisionRunnerProvider;
import decisions.techpreview_samples.loan_validation.loanvalidationdata.Borrower;
import decisions.techpreview_samples.loan_validation.loanvalidationdata.Loan;
import decisions.techpreview_samples.loan_validation.loanvalidationdecisionmodel.Approval_decision_modelOutput;
import decisions.techpreview_samples.loan_validation.loanvalidationdecisionmodel.approval_decision_model.Input;

[..]

DecisionRunnerProvider provider = new ClassLoaderDecisionRunnerProvider.Builder().build();

DecisionRunner runner = provider.getDecisionRunner("approval");

Input in = new Input();

Borrower borrower = new Borrower();
borrower.setZipCode("12345");
borrower.setCreditScore(700L);
borrower.setFirstName("John");
borrower.setLastName("Doe");
borrower.setYearlyIncome(100000L);
in.borrower = borrower;

Loan loan = new Loan();
loan.setAmount(185000L);
loan.setNumberOfMonthlyPayments(72L);
in.loan = loan;

Approval_decision_modelOutput out = (Approval_decision_modelOutput)runner.execute(in);

Alternatively, the input can be created from a map of objects instead of a specific input Java class:

import com.ibm.decision.run.DecisionRunner;
import com.ibm.decision.run.provider.ClassLoaderDecisionRunnerProvider;
import com.ibm.decision.run.provider.DecisionRunnerProvider;
import decisions.techpreview_samples.loan_validation.loanvalidationdata.Borrower;
import decisions.techpreview_samples.loan_validation.loanvalidationdata.Loan;
import decisions.techpreview_samples.loan_validation.loanvalidationdecisionmodel.Approval_decision_modelOutput;

[..]

DecisionRunnerProvider provider = new ClassLoaderDecisionRunnerProvider.Builder().build();

DecisionRunner runner = provider.getDecisionRunner("approval");

Map<String, Object> inParams = new HashMap<String, Object>();

Borrower borrower = new Borrower();
borrower.setZipCode("12345");
borrower.setCreditScore(700L);
borrower.setFirstName("John");
borrower.setLastName("Doe");
borrower.setYearlyIncome(100000L);
inParams.put("borrower", borrower);

Loan loan = new Loan();
loan.setAmount(185000L);
loan.setNumberOfMonthlyPayments(72L);
inParams.put("loan", loan);

Approval_decision_modelOutput out = (Approval_decision_modelOutput) runner.execute(runner.createInput(inParams));