polish model_builder code and samples; tweak C# wrapping code

ortools/linear_solver/samples/AssignmentMb.cs

@@ -30,7 +30,7 @@ public class AssignmentMb
         int numTasks = costs.GetLength(1);
         // [END data_model]
 
-       // [START model]
+        // [START model]
         ModelBuilder model = new ModelBuilder();
         // [END model]
 
@@ -58,7 +58,7 @@ public class AssignmentMb
             {
                 assignedWork.Add(x[i, j]);
             }
-            model.Add(assignedWork <= 1); 
+            model.Add(assignedWork <= 1);
         }
 
         // Each task is assigned to exactly one worker.
@@ -69,7 +69,7 @@ public class AssignmentMb
             {
                 assignedWorker.Add(x[i, j]);
             }
-            model.Add(assignedWorker == 1); 
+            model.Add(assignedWorker == 1);
         }
         // [END constraints]
 
@@ -89,9 +89,10 @@ public class AssignmentMb
         // [START solver]
         // Create the solver with the SCIP backend and check it is supported.
         ModelSolver solver = new ModelSolver("SCIP");
-        if (!solver.SolverIsSupported()) return;
+        if (!solver.SolverIsSupported())
+            return;
         // [END solver]
-        
+
         // Solve
         // [START solve]
         SolveStatus resultStatus = solver.Solve(model);

ortools/linear_solver/samples/AssignmentMb.java

@@ -13,21 +13,23 @@
 
 // [START program]
 package com.google.ortools.linearsolver.samples;
+
 // [START import]
 import com.google.ortools.Loader;
-import com.google.ortools.modelbuilder.LinearConstraint;
 import com.google.ortools.modelbuilder.LinearExpr;
 import com.google.ortools.modelbuilder.LinearExprBuilder;
 import com.google.ortools.modelbuilder.ModelBuilder;
 import com.google.ortools.modelbuilder.ModelSolver;
 import com.google.ortools.modelbuilder.SolveStatus;
 import com.google.ortools.modelbuilder.Variable;
+
 // [END import]
 
 /** MIP example that solves an assignment problem. */
 public class AssignmentMb {
   public static void main(String[] args) {
     Loader.loadNativeLibraries();
+
     // Data
     // [START data_model]
     double[][] costs = {
@@ -92,7 +94,9 @@ public class AssignmentMb {
     // [START solver]
     // Create the solver with the SCIP backend and check it is supported.
     ModelSolver solver = new ModelSolver("scip");
-    if (!solver.solverIsSupported()) return;
+    if (!solver.solverIsSupported()) {
+      return;
+    }
     // [END solver]
 
     // [START solve]

ortools/linear_solver/samples/BUILD.bazel

@@ -36,6 +36,10 @@ code_sample_cc(name = "stigler_diet")
 
 # Model Builder
 
+code_sample_java(name = "AssignmentMb")
+
+code_sample_java(name = "BinPackingMb")
+
 code_sample_java(name = "CloneModelMb")
 
 code_sample_java(name = "SimpleLpProgramMb")

ortools/linear_solver/samples/BinPackingMb.cs

@@ -86,9 +86,10 @@ public class BinPackingMb
         // [START solver]
         // Create the solver with the SCIP backend and check it is supported.
         ModelSolver solver = new ModelSolver("SCIP");
-        if (!solver.SolverIsSupported()) return;
+        if (!solver.SolverIsSupported())
+            return;
         // [END solver]
-        
+
         // [START solve]
         SolveStatus resultStatus = solver.Solve(model);
         // [END solve]

ortools/linear_solver/samples/BinPackingMb.java

@@ -14,15 +14,16 @@
 // MIP example that solves a bin packing problem.
 // [START program]
 package com.google.ortools.linearsolver.samples;
+
 // [START import]
 import com.google.ortools.Loader;
-import com.google.ortools.modelbuilder.LinearConstraint;
 import com.google.ortools.modelbuilder.LinearExpr;
 import com.google.ortools.modelbuilder.LinearExprBuilder;
 import com.google.ortools.modelbuilder.ModelBuilder;
 import com.google.ortools.modelbuilder.ModelSolver;
 import com.google.ortools.modelbuilder.SolveStatus;
 import com.google.ortools.modelbuilder.Variable;
+
 // [END import]
 
 /** Bin packing problem. */
@@ -35,6 +36,7 @@ public class BinPackingMb {
     public final int numBins = weights.length;
     public final int binCapacity = 100;
   }
+
   // [END data_model]
 
   public static void main(String[] args) throws Exception {
@@ -71,7 +73,7 @@ public class BinPackingMb {
       model.addEquality(oneCopy, 1);
     }
 
-    // The bin capacity contraint for bin j is
+    // The bin capacity constraint for bin j is
     //   sum_i w_i x_ij <= C*y_j
     // To define this constraint, first subtract the left side from the right to get
     //   0 <= C*y_j - sum_i w_i x_ij
@@ -95,7 +97,9 @@ public class BinPackingMb {
     // [START solver]
     // Create the solver with the SCIP backend and check it is supported.
     ModelSolver solver = new ModelSolver("scip");
-    if (!solver.solverIsSupported()) return;
+    if (!solver.solverIsSupported()) {
+      return;
+    }
     // [END solver]
 
     // [START solve]

ortools/linear_solver/samples/CloneModelMb.cs

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Minimal example to call the SCIP solver.
+// Minimal example to clone a model.
 // [START program]
 // [START import]
 using System;
@@ -63,12 +63,13 @@ public class SimpleMipProgramMb
 
         Console.WriteLine("Number of constraints in the original model = " + model.ConstraintsCount());
         Console.WriteLine("Number of constraints in the cloned model = " + modelCopy.ConstraintsCount());
-        // [END clone]        
+        // [END clone]
 
         // [START solver]
-        // Create the solver with the SCIP backend and checks it is supported.
-        ModelSolver solver = new ModelSolver("SCIP");
-        if (!solver.SolverIsSupported()) return;
+        // Create the solver with the CP-SAT backend and checks it is supported.
+        ModelSolver solver = new ModelSolver("sat");
+        if (!solver.SolverIsSupported())
+            return;
         // [END solver]
 
         // [START solve]

ortools/linear_solver/samples/CloneModelMb.java

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Minimal example to call the MIP solver.
+// Minimal example to clone a model.
 // [START program]
 package com.google.ortools.linearsolver.samples;
 
@@ -75,9 +75,11 @@ public final class CloneModelMb {
     // [END clone]
 
     // [START solver]
-    // Create the solver with the SCIP backend and check it is supported.
-    ModelSolver solver = new ModelSolver("scip");
-    if (!solver.solverIsSupported()) return;
+    // Create the solver with the CP-SAT backend and check it is supported.
+    ModelSolver solver = new ModelSolver("sat");
+    if (!solver.solverIsSupported()) {
+      return;
+    }
     // [END solver]
 
     // [START solve]

ortools/linear_solver/samples/SimpleMipProgramMb.cs

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Minimal example to call the SCIP solver.
+// Minimal example to solve a MIP problem.
 // [START program]
 // [START import]
 using System;

ortools/linear_solver/samples/SimpleMipProgramMb.java

@@ -56,9 +56,15 @@ public final class SimpleMipProgramMb {
     model.maximize(LinearExpr.newBuilder().add(x).addTerm(y, 10.0));
     // [END objective]
 
-    // [START solve]
-    // Solve with the SCIP MIP solver.
+    // [START solver]
+    // Create the solver with the SCIP backend and check it is supported.
     ModelSolver solver = new ModelSolver("scip");
+    if (!solver.solverIsSupported()) {
+      return;
+    }
+    // [END solver]
+
+    // [START solve]
     final SolveStatus status = solver.solve(model);
     // [END solve]