[Valid Java] 2. when too many constructor parameters exist, define tivejava

[Valid Java] 2. when too many constructor parameters exist, define tivejava

Package cn. xf. cp. ch02.item2;/***** function: when there are many construction parameters out of the controllable range, use build Mode Time: 8:25:05 PM file: NutritionFacts. java ** @ author Administrator **/public class NutritionFacts {private final int param1; private final int param2; private final int param3; private final int param4; private final int param5; private final int param6; private final int param7; public static void main (String [] args) {// initialize NutritionFacts test = new NutritionFacts. builder (1, 2 ). param3 (3 ). param4 (4 ). param5 (5 ). param6 (6 ). param7 (7 ). build ();} private NutritionFacts (Builder build) {param1 = build. param1; param2 = build. param2; param3 = build. param3; param4 = build. param4; param5 = build. param5; param6 = build. param6; param7 = build. param7;} public static class Builder {private final int param1; private final int param2; private int param3 = 0; private int param4 = 0; private int param5 = 0; private int param6 = 0; private int param7 = 0; public Builder (int param1, int param2) {this. param1 = param1; this. param2 = param2;} public Builder param3 (int val) {param3 = val; return this;} public Builder param4 (int val) {param3 = val; return this ;} public Builder param5 (int val) {param3 = val; return this;} public Builder param6 (int val) {param3 = val; return this;} public Builder param7 (int val) {param3 = val; return this;} public NutritionFacts build () {return new NutritionFacts (this );}}}